ajari,
Do you have a MIDI Cable connected when you record?
I was recording some tracks off my 840 last night. I found out that whenever I had my MIDI cable plugged in there were crackling sounds when recording and occasional bop's (as opposed to pops) you could say. Whenever there was a bop, the sound would be blured on playback. Where it crackled was fine.
I checked to see if the sounds were on the original source and they weren't. Even when I wasn't recording and SONAR on internal sync I could still hear these noises. What I tried was playing back the sound with the midi cable out and the sounds were gone. It's as if the MIDI signals being sent/received were some how interferring with the sound..
So what I ended up doing was plugging in the MIDI cable using MIDI clock sync, hitting play then unplugging the MIDI cable and it recorded fine.
Porter