never owned one, so no. what kind of chronic problems? (i'm thinking of seriously looking into them soon, so i wanna know)
Haha, yep I have. I have a small crate practice amp for goofing off by myself (I use my Ampeg for band practice) and I'm pretty sure there's a loose wire or it's just shot. It'll fall to 1/2 volume out of no where and pop back in. I also had a similar problem with an old Peavey full cabinet I used to own. The bottom speaker liked to chime in whenever it felt necessary. Definitely just a loose wire there, but it was tough to get inside seeing that it was fully enclosed and I just ended up parting with it after a few years.
I'm on my third Aguilar component (not speakers) and have no performance issues. My 750 had a couple loose screws inside (just like it's current owner) but that was easily remedied. Me likey me Aguilar!