Given that the OP already owns a DAC and is looking for a low cost fix the following recommendation may not be appropriate to him at this time but may be of interest to other readers anticipating a similar situation.
A multiple channel audio interface, USB or Firewire, is an excellent solution to the problem.
I have the inputs on mine more pr less permanently connected to a PC, two TTs, a receiver (TV, Radio, CD/DVD optical drive), microphone and guitar pick up, Outputs are sent to headphones, desktop monitors, floorstanding loudspeakers and installation speakers in the kitchen. There is also a loopback to listen to or record anything on the PC. Plus a S/PDIF loop to a digital recorder. Obviously there are many other permutations and combinations possible.
The pro audio guys make the best quality devices of this type as they have been doing it for longer for a discerning client base. Prices are surprisingly reasonable. They also usually come with very sophisticayed software EQ and effects packages. You can also use a MIDI control surface to map software controls (mouse, keyboard) to analogue (knobs, sliders).
Top of the range, cannot really get better is something from RME. http://www.rme-audio.de/en_products_fireface_uc.php @ ~ £700.
Middle market alternatives include the MOTU Ultralite http://www.motu.com/products/motuaudio/ultralite-mk3/ @ ~3350.
Focusrite now make a still excellent low cost version. http://uk.focusrite.com/usb-audio-interfaces/scarlett-8i6 @ ~ £175.