Hi!

the tuner isnt an input

Suit yourself. You're more than welcome to believe whatever you like, even
when the tuner is clearly external to the amp.

:-)

What, you think they build
seperate pre-amps for aux and tape inputs?

That very much depends upon the design of the amplifier.

I've tried to offer some help and correction to some beliefs that aren't
universally correct. All the while I've been fairly polite about the whole
thing. I guess there are some people who just can't/won't/don't want to be
told or helped. You seem to be one of those types. So, I won't reply any
further. Good luck with your amplifier, though. I do hope you get it fixed
and working well.

William