"Mark" ) writes:
my GUESS would be that the radio has a bridging type of amplifiers that
drives both speaker leads so as to get more power, and one side of the
amp is defective.

BUt if that's the case, then putting the speaker from one output line
to ground will put a low value resistor across a DC voltage. Not so
good for the speaker, and not so good for the amplifier.

Put a capacitor between the amp and the speaker, and of course it will
be like any single-ended amplifier.

Micahel

I assume this is a stereo radio with a left and right speaker.

How does the other side work?

Mark