Yes, I'm driving both the amp and the sub with just the RCA outputs, you say it should be fine but isn't.
Is there something I can check?
I did swap outputs and the amp is driven fine by both outputs.
the sub does not work on either outputs.
nor does it work by itself without the amp hooked up at the same time, so it doesn't sound like an overloading issue.
I get a more usable signal hooking the sub to the tape output, but I have to turn the sub up way more than before.
the sub works fine when I hook it to another preamp.
does the preamp have an unusual output impedance that the sub doesn't like?
Or in the output circuitry, can something fry, then not allow 2 outputs to work at the same time?