so my amp is making a crackling sound when using high gain. it also does this through the head phone jack. If it was a problem with the speaker would it also come from the head phone jack? I have used two different set of pick ups, two pedals, and different guitars and determined the amp has to be the culprit. I have another amp and it does not do this. Help???
What amp is it? Solid state or valve? If it has Send/Return maybe you can find out if it's the preamp or the power amp. Sometimes it's also just the knobs.
What kind of amp its it? Is is constant or intermittent? Could be your cables this would be intermittent as you move around and the cables are moved, or the amp might have dirty pots which would crackle whenever you adjust them and possibly just due to the vibration of the amp if you are playing through the speaker.

A faulty speaker would be bypassed when you use headphones so I doubt that is the issue. Check your cables.
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its a orange crush 20l so it is a solid state. it does not crackle when i turn the knobs only when i play with a high output pickup with some high gain. it gets buried in the mix but you can hear it. i am going to run more tests today when i get the time. it might just be my digitech pedal.