Help - Adcom GFA-545 works in mono only

I just got my Adcom GFA- 545 amp from eBay, that's I'm using to power NS-10Ms for a studio solution and I noticed that the amp works in mono only, regardless of source panning.

Both RCA inputs are ok, I tried plugging only one and panning worked as expected - no sound when panned hard one side, normal sound when panned to the other, so there appears to be mono summing going on inside the amp.

The other thing I've noticed is that the right side of the amp runs significantly warmer than the left, which is barely emitting any heat.

Do you have any suggestions as to how to resolve this?
Sounds like one side of the amp is dead. Is it fused? Check the fuses
It's broken. You should contact the seller, tell him it is broken and get your money back.
Ok, thanks for the replies.

It's a little weird that the signal is coming out as mono from both sides, if one side would be dead.
Sounds more like somebody did a rewiring job or something... or is that a wrong assumption?
I would possibly suspect 'a' previous owner blew one side out, rewired it to run both speakers off the one working side. and then passed it off as a working amp.
So you have half an amp doing the job of both.
Whomever sold it to you perhaps? never knew it is messed up. Your best choice is to return it while you can. If you cannot return it. i would think it will cost you as much or more to fix it, than to find another used one.
Next time make certain you have a recourse, if you are stuck with a lemon. You may feel you want to 'save' your purchase, but if you can return it, do so. It is not as advertised, and if they only guaranteed to be not DOA, it IS DOA, in one channel. If it was sold "as is", then i think you have a partially useful doorstop.
This is, of course only a guess as to what the problem is. Since only paying someone $100. just to look at it, and is not even a start at actually fixing it...
don't look back, not worth it, very unlikely you'll get satisfaction
Baloney...if it doesn't work in stereo GET YER MONEY BACK! Ebay (and Paypal) are supposed to protect you...and I bet the seller would prefer a return over being blasted with a bad review.
If you used your CC thru paypal, you can ask for a chargeback even if paypal rules in favor of the seller. The CC company is who makes the final decesion. Also put in a negative to help others. I had to do so (I really hate doing that) recently for a filthy steel top plate for a Linn Sondek TT. I felt bad about it till two weeks later, when the seller got 2 more negs then got suspended. No need for you to be stuck. Happy listening.
Thank you all for the help.

The seller has been great about it and I will be returning the amp.
That is great news. Hope you can find another good amp soon. Look here on AudiogoN.
Jacentys, that's good of the seller. Leave a positive feedback, since he cares about what he sells. Good luck.
The last 2 audiogon items I attempted to buy were confirmed purchases followed by, "Oh...sorry man...I sold that last week"...and this has never happened elsewhere. I did have a couple of other successful a'gon purchases though. Ya never know...
there appears to be mono summing going on inside the amp.
Is it possible you have this amp switched into a "bridged mono" mode?
I was looking in the manual and there is no mention of such switch.

If that is the case, then I'm guessing there was some manual rewiring going on but I'm not good enough with electronics to troubleshoot that.
Too much reflection on the current state of affairs... see prior post