Mono Button Not Working When Tape Monitor 2 is Engaged

[Bongo Beater]

I have a Pioneer SX-650 amplifier/receiver.

The amp includes a mono button and two tape monitor options.

The mono button works when neither of the tape monitors are engaged, and it also works when tape monitor 1 is engaged. But the mono button does not work when tape monitor 2 is engaged.

I am assuming that it should work with both. Is this something that can be repaired?

 

[Mr Peabody]

If you can find an online manual or still have yours you should see what the 650 is supposed to do. If something is wrong I'm sure it can be fixed if you find a tech who works on vintage receivers.

Just curious what you use the tape monitors for, cassettes, etc.?

 

[Bongo Beater]

If you can find an online manual or still have yours you should see what the 650 is supposed to do. If something is wrong I'm sure it can be fixed if you find a tech who works on vintage receivers.

Just curious what you use the tape monitors for, cassettes, etc.?

I alternately used tape monitor 1 over the years with either a free-standing CD burner/player or with an EQ unit. I have two sets of speakers in two different rooms. I am currently using tape monitor 2 with a different eq unit specific to one set of speakers. The mono button is not working with tape monitor 2, so I have been using a Y converter in the chain when I play mono LPs. I just thought this was strange, as the mono button works with tape monitor 1. You're right, I should find the manual. Thank you for the reply!