Balanced to unbalanced connection might be your problem.
Depending on the balanced audio device output design and the ability to current limit active devices in the case of output short circuit, the following scenario may develop:
[image|3624353]
This is clearly not desirable, especially for active device outputs. Permanent damage may occur. If unsure, don’t do it. You have been warned.
read more [link|https://www.superbestaudiofriends.org/index.php?threads/audio-balanced-output-to-unbalanced-input-a-brief-visual-guide.7012/|here]
I don't see any signs of magic smoke release, and without a schematic it would be very technical and time consuming to find the problem.
The issue is likely a blown output IC. You would have to figure out which IC that was and scope its i/o to verify.
All this is assuming the problem isn't something overloaded and blown in your HiFi.