Check the playback properties and see if your line in is enabled and turned up.
You should be using the line in connection for the preamp (right?)

It is most likely your line in is muted or turned down in the playback section, while be turned up in the record section of the soundcard mixer. That would expain getting a good signal and not hearing it.

Just to mention - 512 RAM is pretty small amount for audio, but if it is working well for you, that's cool.

For metronome isuue (click). Check Options-metronome, or click the metronome icon at top.
There are checkboxes and numeric settings to make it do whatever you want.

I do not work here, but the benefits are still awesome
Make your sound your own!