Troubleshooting intermittent recording issue:

J-Bot

New member
Hi folks, so I've been helping an acquaintance of mine get set up for recording his drum kit at home so he can record some halfway decent demos. I've been walking him through the signal chain, and tutoring him on recording with Reaper. (later we'll get into a bit of mixing, but that's a whole other can of worms!)

He has mentioned an intermittent problem while recording. I haven't noticed it when I'm on site, but I only had him play a couple minutes to set levels and adjust the mic positions a little, as well as doing a scratch recording while playing to a drumless track that was imported into a track in Reaper.

The problem that he mentioned is that every half minute or so while recording (it's not exactly every 30 seconds, but roughly that time frame) the system "hiccups". It basically freezes for a split second before continuing, and when it freezes, there is an audible pop like someone thumping a mic. He was asking me if he should put a filter in, or if it's a problem from unclean power. I told him let's research a bit more before spending money on a solution that might not work.

He did say it happens while recording, but he doesn't recall hearing the problem during playback. He's going to send me a rendered mp3 of the recording soon to see if the sound from the interruption is captured or not. (I'm assuming it won't be).

The signal chain is as follows: Mics -> XLR cables -> Snake -> Focusrite Scarlett <-> PC
Scarlett Output 1 and 2 -> powered JBL Monitors

SM57's on the snare and on the floor tom. Rode M5 SDCs as overheads, Beta 52 on the kick. He had some older XLR cables from his PA system on hand, but they weren't quite long enough to reach the interface, so I recommended he either get longer cables, or just get an 8-channel cable snake like the one I brought out (basically 8-channel cable snake 8 heads on each end). He ended up getting a snake that terminates in kind of a stage box strip at one end, XLR leads on the other end, which plug into the interface. So I just worked with it, connected the mic cables to the 8-channel strip. Seemed to be fine, got good signals at the interface and in the DAW. Didn't sound too bad, just need to tweak mic positions next time I'm over there.

For the interface, he's using a Focusrite Scarlett 18i20 Mk2 connected to his PC via USB 2.0, running Windows 10. 1/4" Outputs from the AI are running to a pair of powered JBL monitors. His system, firmware, drivers, and Reaper are all up to date. Everything seemed fine when I was setting levels and having him record a bit to a drumless track he had. And for the few minutes I had Reaper recording, I didn't notice anything out of the ordinary.

On the Scarlett, the Channels 1-4 have the +48v enabled for the Rode M5's.

Unfortunately, I won't be meeting with him again until April, so I won't be able to troubleshoot each piece of the signal chain or try to reproduce the problem or witness it in person until then.

I don't know off the top of my head what's happening. My first thought is a power or device interruption involving the Scarlett. Seems like an audio interface going offline or being interrupted might hang Reaper briefly. I mean, I've seen cases of a VST taking a dive causing the DAW to hang or crash, so an interface being interrupted somehow might cause that "hiccup". Any insight on this would be appreciated. Meanwhile I'll keep trying to search around for similar issues and if they were resolved or not.

Thanks!
 
My first thought would be to check the computer j-Bot. You don't give us any specs but assuming it is of decent speed/ram etc get him to check the usual suspects..
Wireless network adaptors, disable them. Check what is running on the PC at start up and if he doesn't need it, stop it. Run Latencymon.

He needs to be very systematic, for instance run just two channels with mics and if the problem does not show, does it happen as the channel count increases? That would be an indication of lack of resources or, resources being gobbled up elsewhere. PC Audio 101 I know but is the internal sound card disabled? Windows sounds, bleeps and bloops stopped? Make sure the USB port does not share with anything else.

Lastly, get him to organize his problem and put it to Focusrite. Their technical backup is very good.

Dave.
 
I agree with Dave, there is something running, virus scan (they often run when creating new files), WIFI, but something is running and hogging the resources.

Find that and most likely the problem goes a way. It could also be your hard drive is too slow and it is trying to catch up writing to the disc. If that is the case, faster HD or more RAM. Probably not the problem, but if everything else fails to expose the problem, HD speed might be the next step to investigate.
 
I agree with Dave, there is something running, virus scan (they often run when creating new files), WIFI, but something is running and hogging the resources.

Find that and most likely the problem goes a way. It could also be your hard drive is too slow and it is trying to catch up writing to the disc. If that is the case, faster HD or more RAM. Probably not the problem, but if everything else fails to expose the problem, HD speed might be the next step to investigate.

Could be HDD but, AFAIK "everything" gets loaded into ram and the hard drive just "rescues" it as needed? Chap might have marginal ram? Ten wants about 2G just to get out of bed? Then, memory can fail, you can download a checker but they take a while!

Dave.
 
Thanks. Yeah, that could be the case. Possibly something in the background spinning up every half minute. I'll have to take a look at the task manager while he's recording next time. I don't know the PC specs off the top of my head, but I'm pretty sure it's on an SSD, at least. Intel Core processor of some type. At least 4GB RAM, possibly more, but I'm not positive. I'l need to check the specs next time I'm over there. He's an architect by trade, owns his own firm, and runs CAD software on his home machine, also creates and edits blueprints.

So yeah, I'll monitor usage in Reaper, keep the task manager window open while recording, and see if behavior changes when reducing track count. Quick easy checks. If those don't turn anything up, I might have to start looking at something in his house turning on or off coinciding with the thump/freeze problem. Which a Furman might take care of that. Right now he's just plugged into a power strip which I'm not 100% sure has build-in surge protection.
 
If he has an SSD, even if the RAM is low, those are fast enough to do IO for writing (IMO) and if he is doing CAD on the same machine, then you can bet he has enough HP.

After readying your last post, I think something is running in the background causing it to do this. My suspicion would be a virus scanner. But could be multitude of things. You running the task manager will help the most.
 
Thanks. Yeah, that could be the case. Possibly something in the background spinning up every half minute. I'll have to take a look at the task manager while he's recording next time. I don't know the PC specs off the top of my head, but I'm pretty sure it's on an SSD, at least. Intel Core processor of some type. At least 4GB RAM, possibly more, but I'm not positive. I'l need to check the specs next time I'm over there. He's an architect by trade, owns his own firm, and runs CAD software on his home machine, also creates and edits blueprints.

So yeah, I'll monitor usage in Reaper, keep the task manager window open while recording, and see if behavior changes when reducing track count. Quick easy checks. If those don't turn anything up, I might have to start looking at something in his house turning on or off coinciding with the thump/freeze problem. Which a Furman might take care of that. Right now he's just plugged into a power strip which I'm not 100% sure has build-in surge protection.

I started a thread a few weeks ago over at soundonsond.com asking whether people had much trouble with "dirty" mains supplies. The resounding response was that they don't. A very few live in quite remote rural areas and have the odd power outage but almost no one reported recording gear problems that they could put down to mains borne glitches.

This is UK power of course and I understand the US is rather less well served? I would still say that any mains borne problems would cause other equipment to show problems as well? My experience is that computers and attached equipment is pretty well protected?

People are always happy to take your money for filters and surge suppressors of course but are they flogging you a solution to a non-problem?
Be good to hear from anyone who has positive, documented proof of mains "spikes" causing issues?

Dave.
 
I started a thread a few weeks ago over at soundonsond.com asking whether people had much trouble with "dirty" mains supplies. The resounding response was that they don't. A very few live in quite remote rural areas and have the odd power outage but almost no one reported recording gear problems that they could put down to mains borne glitches.

This is UK power of course and I understand the US is rather less well served? I would still say that any mains borne problems would cause other equipment to show problems as well? My experience is that computers and attached equipment is pretty well protected?

People are always happy to take your money for filters and surge suppressors of course but are they flogging you a solution to a non-problem?
Be good to hear from anyone who has positive, documented proof of mains "spikes" causing issues?

Dave.

Hey Dave.......

I was a field tech for a large electronics firm here in the US for 37 years. In our practice we employed line monitors and a number of other devices when we thought a main power line might be an issue. Those monitors measured and recorded line activity of all kinds.....including spikes (surges)....line noise (dirty line)....etc...etc. The later models were excellent and extremely accurate. Long story short.........as for dirty lines......that was really fairly rare.......with the exception of a water cooler motor or the like causing some noise adjacent to our product. Supply lines were not dirty to speak of. Surges....and spikes however......were the leading cause of component failure.......as you likely know......with weather related issues being the cause many times. A Florida thunder storm always meant some board failure.
 
Hi folks, so I've been helping an acquaintance of mine get set up for recording his drum kit at home so he can record some halfway decent demos. I've been walking him through the signal chain, and tutoring him on recording with Reaper. (later we'll get into a bit of mixing, but that's a whole other can of worms!)

He has mentioned an intermittent problem while recording. I haven't noticed it when I'm on site, but I only had him play a couple minutes to set levels and adjust the mic positions a little, as well as doing a scratch recording while playing to a drumless track that was imported into a track in Reaper.

The problem that he mentioned is that every half minute or so while recording (it's not exactly every 30 seconds, but roughly that time frame) the system "hiccups". It basically freezes for a split second before continuing, and when it freezes, there is an audible pop like someone thumping a mic. He was asking me if he should put a filter in, or if it's a problem from unclean power. I told him let's research a bit more before spending money on a solution that might not work.

He did say it happens while recording, but he doesn't recall hearing the problem during playback. He's going to send me a rendered mp3 of the recording soon to see if the sound from the interruption is captured or not. (I'm assuming it won't be).

The signal chain is as follows: Mics -> XLR cables -> Snake -> Focusrite Scarlett <-> PC
Scarlett Output 1 and 2 -> powered JBL Monitors

SM57's on the snare and on the floor tom. Rode M5 SDCs as overheads, Beta 52 on the kick. He had some older XLR cables from his PA system on hand, but they weren't quite long enough to reach the interface, so I recommended he either get longer cables, or just get an 8-channel cable snake like the one I brought out (basically 8-channel cable snake 8 heads on each end). He ended up getting a snake that terminates in kind of a stage box strip at one end, XLR leads on the other end, which plug into the interface. So I just worked with it, connected the mic cables to the 8-channel strip. Seemed to be fine, got good signals at the interface and in the DAW. Didn't sound too bad, just need to tweak mic positions next time I'm over there.

For the interface, he's using a Focusrite Scarlett 18i20 Mk2 connected to his PC via USB 2.0, running Windows 10. 1/4" Outputs from the AI are running to a pair of powered JBL monitors. His system, firmware, drivers, and Reaper are all up to date. Everything seemed fine when I was setting levels and having him record a bit to a drumless track he had. And for the few minutes I had Reaper recording, I didn't notice anything out of the ordinary.

On the Scarlett, the Channels 1-4 have the +48v enabled for the Rode M5's.

Unfortunately, I won't be meeting with him again until April, so I won't be able to troubleshoot each piece of the signal chain or try to reproduce the problem or witness it in person until then.

I don't know off the top of my head what's happening. My first thought is a power or device interruption involving the Scarlett. Seems like an audio interface going offline or being interrupted might hang Reaper briefly. I mean, I've seen cases of a VST taking a dive causing the DAW to hang or crash, so an interface being interrupted somehow might cause that "hiccup". Any insight on this would be appreciated. Meanwhile I'll keep trying to search around for similar issues and if they were resolved or not.

Thanks!

Sounds like a buffering problem.

Else there is something else running that interferes.
You must close EVERYTHING that is not the program used to record with.
EVERYTHING. NO EXCEPTIONS.

Especially on win8 and 10 there is way too much social media krapp that sucks out too many cycles doing useless things. DELETE THEM ALL if you plan to use that box for audio recording.

Turn off all antivirus and everything else that is not needed to make the recording.
 
Hey Dave.......

I was a field tech for a large electronics firm here in the US for 37 years. In our practice we employed line monitors and a number of other devices when we thought a main power line might be an issue. Those monitors measured and recorded line activity of all kinds.....including spikes (surges)....line noise (dirty line)....etc...etc. The later models were excellent and extremely accurate. Long story short.........as for dirty lines......that was really fairly rare.......with the exception of a water cooler motor or the like causing some noise adjacent to our product. Supply lines were not dirty to speak of. Surges....and spikes however......were the leading cause of component failure.......as you likely know......with weather related issues being the cause many times. A Florida thunder storm always meant some board failure.

Well of course we don't get anything like those storms in either frequency or intensity but I did see my share of lightening damage. There was a bit of a "process" TVs with switch mode power supplies were usually totally borked but the earlier VCRs with a ~20va 50Hz mains traff usually just had the input fuse of about 315mA blown black and suffered no further damage. Then VCRs went SMPSUs and got buggered!

Dave.
 
Yeah, agreed. I'm not really suspecting the power unless his house somehow isn't supplying enough amperage to that particular circuit or something. Given what his house is like, I'll just say that is highly unlikely. (it's a McMansion) The power itself is probably fine, which is why I told him we should research the issue and troubleshoot instead of going out and buying a filter. Even if the power was a little dirty, the worst we'd probably get is a little hum on the line or something.

I'm a native Floridian, so yeah, lightning storms are a thing down there. Here in Philly, (well, the suburbs) we get some occasional storms, but nothing like Florida.

But yeah, I agree with it most likely being a computer issue. I don't really suspect the power, and that would be the absolute last thing I would check. My bet is some program or service firing up and stealing priority from Reaper or something. As I said, I'll check task manager, and see if any services jump to the top of the CPU usage and/or RAM usage. I'll just arm the tracks, and set it to record for 10 minutes or so, and keep an eye on things when the "hiccup" happens.

FWIW, I did read the SOS article on recording interruptions and probable causes, which pretty much covered the gamut of issues. So I've got a few ideas where to start looking when I see him again in April.

Thanks all, for pointing me in the right direction, and also for reconfirming some of my suspicions.
 
Okay, bumping this with an update.

So I was over at his place today, and did manage to witness the "blips" first hand. It's just a split second kind of digital glitch or maybe artifact kind of sound. He claimed he usually heard it much more often than we did today, but I did catch it twice over the course of several minutes. Very intermittent, couldn't really force it to happen by clicking around the timeline while playing back. I didn't really see anything abnormal stealing CPU cycles in the task manager when it happened. Nothing real obvious jumped to the top, and CPU idle was 98%

Specs wise, it's a pretty beefy computer, though it does seem to be a Dell related PC (I'm not fond of Dell, so if anyone in particular favors that brand, I'm sorry, and I hope you find a better brand someday). ;)

His CPU is an Intel (forget which model/generation but something like 3.2GHz per core) 16GB RAM, but he was on a normal HDD drive, NVidia GPU (didn't check what model, but it shouldn't matter too, too much) It's a computer he brought home from his business since it wasn't being used there anymore. It has a wireless adapter on the back for connecting to the home network.

I disabled a number of services, and set the rest to manual in the services manager, going by Black Viper's guide for Win7. He's using Win7 Pro.

I'm hoping that helps mitigate the occurrence of the interruption during recording and/or playback. And yes, the hiccups were happening during simple playback, not only while recording. (I also disabled any Nvidia and Realtek HD Audio based services and devices, just to make sure ALL audio is handled by the Focusrite interface).

His security software (AV/Malware/firewall/etc.) is Trend Micro. It could be very well that is a potential culprit, and I might recommend he uninstall that and get something like Avast since I've had no problems with it, and my own PC isn't too far off specs wise from him. He IS using a regular HDD drive, but I couldn't check the spindle speed in device properties, so not sure if it's 7200 or 5400RPM. I SERIOUSLY doubt it's a 10K RPM speed.

FWIW, my own HDD, which is currently just being used as a storage drive since I moved OS to an SSD, was a 7200RPM 300GB Western Digital drive, and I've used it for 10 years without any hiccups or hitches/interruptions/artifacts happening during record or playback functions. Could be very well that Dell through a sub-par OEM HDD in the machine.

So hopefully shutting down and setting various services to manual will alleviate some of the hitching while recording and playing back audio. One thing I forgot to check was if there was any mismatch between recording/playback quality on the Focusrite vs. project settings in Reaper. Also, as a test, next time I might bump the buffer up a notch to 256, and see if that has any effect. Didn't sound like buffer underrun or audio dropout to me, though, more a sharp/bright digital glitch or artifact sound, not a crackle or pop.

In a nutshell: definitely some gremlin in the system. Definitely system related. Not entirely sure of the root cause yet, but hopefully my going through things with a fine toothed comb will at least mitigate how often it occurs.

I probably spent about an hour and a half going through everything, and another 2 hours helping him, and doing a little teaching, having him take notes. Unfortunately, I probably won't be able to get back over there until our house hunting adventures are done and we close in July. Though I'll try to respond and go over there if there is any emergency.
 
I gave up Avast (ye lubbers!) years ago, it got very bloated and intrusive I found. I have had Ms Securtiy Essentials on all my machines for a good 6 years with no trouble. I run the free version Of MalwareBytes about once a month, it rarely finds anything.

Might be an idea to run a full "discchk" at turn on once? That is going to take SOME time to run however. Don't see the word a lot these days now with SSDs so common but he could do a defrag.

Dave.
 
As a matter of curiosity, does the mouse freeze at the same time?

If so, it's worth trying a different mouse. I mention this because for a short while I was getting random and momentary freezes which included the mouse. When I put in a new mouse they went away. I don't think this is what's happening in your case, but it is an easy thing to check.
 
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