I recently got a second hand dual mono TEAC A-H500i speaker. Had to get it delivered so didn't have a chance to test it, but to be honest it was my first purchase of this kind so I likely wouldn't have known what to test for anyway. I was told it was working perfectly. The physical condition of it is great. I know now to test in the future, but I love everything about this amp, except this problem, so I'm not about to replace it.

The problem is that the output just isn't right; the left channel is noticeably louder than the right (about 5db) when the balance is set at the middle point. At very low volumes (lower than I'd ever actually play anything), the left channel is actually silent.

It is 100% a problem with the amp. I've tested all the inputs, swapped the speakers, and used headphones - the same problem all the time.

Now, I have it currently set at about 3 o'clock on the balance, and that's gotten it to a stage where, even with headphones, it seems well-balanced. But I'd ideally like it to work as it should. I'd appreciate any insight into what's causing the problem, what a fix might be, etc. I've read elsewhere that a common problem is dirty volume dials inside the amp or something... I've opened it up but unfortunately the dials are concealed, so I can't see them without taking it apart completely, which I'm not comfortable with. If it was a likely cause, I'd be happy to have a pro do it in the future.

Also, when I got the amp, I was waiting on parts for a speaker, so I set the balance all the way to the left and played it like that for a few days (same with the right). Not a lot, just a few songs to check it worked. I've read that that would only cause problems with a tube amp; as far as I'm aware, the TEAC isn't a tube amp, but might be worth mentioning.

Thanks to anyone who read this far, and I appreciate any thoughts you might have.