#1
My Classic 30 makes a weird "pounding" sound when I play sometimes. It sounds like, well...pounding! It's pretty loud, so it definately needs to be fixed. It this a tube or speaker problem?
Gear:
Gibson Vintage Mahogany LP
Line 6 Echo Park
Peavey Classic 30
Seagull Entourage Mini Jumbo
Vox V847A Wahwah pedal
#2
I think your input jack maybe is a bit loose..
Squier Standard Telecaster.
Random Ibanez GIO superstrat
Takamine EG440C Maple Blue

Line 6 Spider III 30 w
Blackheart Killer Ant
Blackheart Little Giant

Line 6 Pod X3 Live
Line 6 Toneport UX-2
#3
Maybe it's your neighbor pounding on the wall every time you crank it up.