Just bought a used Orange AD30. I've had it for a week now, and I've played it probably half a dozen times. The entire time I've played it, I've thought that the volume was a little weak, given it's 30 amp rating (noticeably quieter than my 22 w DDRI). But the tone was great, so I wasn't too worried. It's a basement amp, anyway. However, I was just playing it, and after about ten minutes of play, the volume suddenly jumped drastically. It's now playing at a volume much, much louder than it's been playing for the last week. Usual suspects?