Hi, I've had some problems with my amp, and when I called the local tech shop on the phone they said that it was likely a blown transformer and would cost $300 to fix. The local tech shop is also notorious for ripping people off, so I wanted to check with my trusted talkbass community to see what you guys think before I shell out. This actually happened on my guitar amp - but I swear I'm usually a bassist. I was playing a Fender Bandmaster VM (the reissue, not the classic bandmaster) As it stands right now, my amp will only give me a BIT of volume when it's cranked to 10, and nothing noticeable on lower settings. The tubes and LEDs, all light up fine, there were no bad burning smells, and everything looks OK inside the amp. (I took it apart just to check) What happened was, I was playing this amp (through a different cab than usual actually), and it started sort of suddenly getting much quieter when I hit a certain volume, like almost 'bouncing' off this volume 'limit', dropping suddenly down to a much lower volume before rising back up again, until it hit that apparent limit and bounced back down again. These cycles took about 5-10 seconds each. I went back to try it again this morning, and the amp wouldn't give me any sound, except for a really low volume when it was cranked to 10, as I said above. The cab I was playing through is a strange old unlabeled cab, 1x12 and 1x15. I assumed it was 8 ohms, and was told this when I bought it on craigslist for cheap, but I suppose its possible that it could actually be a 4 ohm? The output on my head is 8 ohm. I have tried different speaker cables, different patch cables, a different guitar, as well as a different cab (AFTER the 'damage' was done), all to no avail. Please let me know if you have any idea what this could be, or if there are any possibilities that you think could be eliminated! I really don't want to let these guys rip me off again. Thanks so much!!