Last time I played my DT50 head was about 3-4 years ago. It was working fine then. It's been powered off since then and stored inside my house. It hasn't been disturbed in any way. A couple days ago, I tried to power it up again (in standby mode, of course) and it exhibited the following behavior: - Power light turned on for a brief moment, then quickly faded out. - None of the white lights on the front panel indicating what channels and modes are selected lit up. - After a couple minutes, I switched out of standby mode and a bunch of noise came out of the speakers (a single 8 ohm cabinet plugged into one of the 8 ohm outs). I could not hear the sound from my guitar when I strummed it. I also previously verified the guitar and cable are working properly. Other info: - Both externally accessible fuses were/are good (tube protection + IEC fuse). - Power tubes were glowing. - It repeats the same behavior every time I power it on. Anyone have any ideas what could be going wrong? I don't think it's the output transformer (a common issue with these amps, apparently) because the fuses are not blowing.