Doing a daft thing:~

[Bob Meadows]

Volv 240 1988:~
Original radio etc.

For some time I had a discrepancy between the front door speakers in terms of volume ie it seemed to jump from one side to the other.
Checked the speaker connections whist doing other work inside the doors-all fine- next stage I thought- a fault in the wiring at the back of the radio.

Whist sitting in the car the other day and studying the radio buttons in better detail I noticed the one for Mono & Stereo, yes you got it!
Should I get my coat now?
Bob.

[Othen]

Originally Posted by Bob Meadows

Volv 240 1988:~
Original radio etc.

For some time I had a discrepancy between the front door speakers in terms of volume ie it seemed to jump from one side to the other.
Checked the speaker connections whist doing other work inside the doors-all fine- next stage I thought- a fault in the wiring at the back of the radio.

Whist sitting in the car the other day and studying the radio buttons in better detail I noticed the one for Mono & Stereo, yes you got it!
Should I get my coat now?
Bob.

Wonderful Bob.
Alan

[Laird Scooby]

Originally Posted by Bob Meadows

Volv 240 1988:~
Original radio etc.

For some time I had a discrepancy between the front door speakers in terms of volume ie it seemed to jump from one side to the other.
Checked the speaker connections whist doing other work inside the doors-all fine- next stage I thought- a fault in the wiring at the back of the radio.

Whist sitting in the car the other day and studying the radio buttons in better detail I noticed the one for Mono & Stereo, yes you got it!
Should I get my coat now?
Bob.

That button only functions on FM radio reception, it doesn't alter the amplifier output. As FM stereo needs a much stronger signal to give both channels you can manually defeat the stereo reception by pressing the mono button to improve reception.

That said, most radios from the early-mid 80s will also auto-revert to mono reception in poor signal areas so it's possible that is what you've been hearing. Would also be an idea to check the balance control is in the centre so you don't get any "false positives" during testing.

Note that some radios (consult your ICE manual for confirmation if yours is one of those) also used the mono button on AM as a sensitivity control - AM broadcasts are of course always mono.