Chosen Solution
I have a Hohner Panther Mega 10 guitar amp- its only giving a mono output on the headphone? My Yamaha GA-10 amp works well, so it must be something to do with the Hohner headphone output? Any ideas?
very often you find a broken solder-connection close to te receptacle. It can easily be resoldered. You might try some cleaner before, maybe there is just a bit of dirt inside.
