Recently picked up an Ashdown EVO 300, LOVE the tone, in the short amount of time I've had it it's solely been plugged into an Avatar 112 8ohm cab, used twice during rehearsals. The first time around no issues whatsoever but at practice the other day after about a half hour of steady playing at 50% volume, a weird sound became audible when plucking the strings on my P Bass... everyone in the room assumed the speaker was toast in the cab (it's about 10 years old, been used a lot)... kind of sounded like a bowl of marbles or broken glass vibrating. Sorry to sound like a noob, I just can't find a better way to describe it... I toughed it out for the duration of the practice, and then yesterday brought my Eden 410 cab as a potential backup, but started the day using the Avatar again, this time with my loyal and faithful Thunderfunk TFB420 amp, to troubleshoot if it was the speaker that was messed up. No weirdness at all, so I'm gathering it's the Ashdown head I just acquired. If it really is the amp, what on earth could be going on inside?