Help! Scott 350R no FM

Hi guys! I have a lovely old Scott 350R receiver in very good condition. Everything works EXCEPT FM. No sound whatsoever. Used an antenna, of course, and tuning gang is clean (clean enough for AM to come in, anyway, though not very well)--Both channels play equally strong (after resoldering some connections).

Any ideas? Don't have the schematic and not sure I could read it if I had it! And yes, stereo is plugged in when I'm trying FM!

Thanks for giving me a look!