i recently acquired a used mesa express and it has just started making a crackling noise in channel one, the clean channel. here's a video:
i'm a noob at this stuff so i'm not sure what the problem is, nor the rememdy. hopefully one of you guys can help me out. should i replace the tubes or take it to a tech? (it's still under mesa's five year warranty).
i should mention that it only started making this noise when i was adjusting the treble knob today; it randomly started. as well, channel two is without any noise or crackling.