Here's a recommendation from Dave Phillips who has a
book on PC sound for the Linux world:

Yamaha DMP11 or an item from Mackie.

Bill, I have been wanting to set up home studio components for
quite a while but I haven't gone beyond some crude (but
efficient) speaker building.

The Fitzmaurice forum has a lot of musicians in it.
They may know a good direction to go if you tell them what
you want to do.