Troubleshooting '69 JMP: popping noise on some sustained notes (sound example included)

[LPman]

I have just noticed after shooting a demo of my '68 SG that between 2:10 and 2:30 there are artifacts during some of the sustained high notes. Sounds like popping noises. You can hear it very clearly right after 2:22 during that huge bend, I timestamped it in the video below.

Today I noticed it again while playing. The amp does it only at very high volume levels when I bend and sustain certain high notes on the guitar. I have not tested it with humbuckers but the amp does it with both of my P90 equipped guitars. There are no other signs of problem with the amp. What the hell could it be?

Can anyone ID this problem?

 

[mAx___]

Not saying it's not the amp but I had a similar problem a while ago and the crackling ended up being the microphone. Took me a while to find out.

 

[FleshOnGear]

That’s weird. It sounds like a bad cable, but I imagine it would do it even if you weren’t playing if it were the cable. I know you singled out the high bend as the place where it’s most audible, but does it happen while playing in other registers?