Suddenly Lost Stereo Buss Monitoring On The 388

[Mark7]

I guess they are passing signal to PGM 2 because I can see the needle move on the meter each time. What's not happening is the signal then being passed to the monitor section from either the buss or the track.

Also, are you referring to this?

So, this morning I connected a mic to channel 2, did the usual things, pushed both buss faders into the unity zone and then put tracks 1 and 2 in rec ready mode with the respective monitor controls at the same level for each track (around 3 O'Clock). I then swept the pan from left to right and it definitely lost volume (practically inaudible) when panned fully right (track 2). I then proceeded to swap buss 2/track 2 out for busses/tracks 4, 6 and 8 with the same monitor gain setting on each. No loss of volume at all. For completeness' sake I did the same with 3, 5 and 7. No probs

Because I only did that from channel 2. Today I used all 8 channels.

 

[Mark7]

Okay. Here goes. I'm using my compressor as a level meter (in bypass mode)

Channel 1: Clapping from across the room I can see the green LEDs on the compressor moving in time with my claps
Channel 2: Same. No sign of any loss of volume
Channel 3: Ditto
Channel 4: Ditto
Channel 5: Ditto
Channel 6: Ditto
Channel 7: Ditto
Channel 8: Ditto

I also tried listening via the aux buss (suggested by someone else, elsewhere). Here are the results

Channel 8: Ja, sehr gut
Channel 7: Oui. tres bien
Channel 6: Not good. Some sound, but lower than channels 7 and 7, and some distortion
Channel 5: I have sound through the main monitor buss (and the needle on track/pgm VU meter 1 is moving), but no sound from the aux buss
Channel 4: No sound from main monitor or aux buss. VU not responding
Channel 3: Same as 4
Channel 2: Same as 4
Channel 1: Same as 5

Maybe this is the post that's causing the confusion. At no point during the first set of tests was I actually listening to what was going on, Also, at this point I still thought that some kind of summing amp had been fried. Obviously that wasn't the case. Then, in the second test I was mostly listening through the Aux/Cue Buss. I only switched to the stereo/main monitor buss for about two channels. Should have been more diligent.

 

[Mark7]

At a glance, how do these caps look?

 

[sweetbeats]

At a glance, how do these caps look?

Well, they look dirty…but if you’re specifically wondering about the stuff around the base of them that’s just adhesive used during manufacturing to hold them in place before soldering.

 

[Mark7]

I gave them a dust. Just wanted to check that wasn't cap leakage.

This morning tried to run signal out of PGM Buss 2 Out to a headphone amp. Just got noise.

Do you think cleaning Monitor gain 2 pot might help?