Just bought an Ashdown ABM500 Evo III on Reverb. I bought this amp knowing the subsonic feature did not work although everything else was supposed to be A-OK. The pots and sliders are a little scratchy but no big deal. The problem: * If you engage the mute function and then turn it off, it takes about 2 full minutes before you get any sound; almost like the tube is warming up but that isn't the issue. The VU meter reads signal during this no sound time and turning the tube off doesn't make it work. * If you remove the instrument cord and then pug it back in, no sound for approx. 2 minutes. * The same happens if you disconnect the speaker cable when the amp is on (with no signal). Tone is excellent but the compressor is whacked. It kills volume in a big way even with light compression. I paid $300 for the amp which came with a new flight case so if the fix is cheap, it might be worth keeping. Any ideas?