42" LG Plasma TV + Apple Airport Express + Bose Wave System

If I remember correctly, the Bose Wave Radio only has one external 3.5mm input so if you want to use multiple sources you will have to use some sort of switching device or manually change the input cable from each device when you want to use it.

You didn't mention if you were using a satellite, cable box, antenna, DVD, etc. If you can be more specific I can help you.

This is the easiest and most cost effective way to do what you want to do.

Buy this: http://www.monoprice.com/products/product.asp?c_id=102&cp_id=10229&cs_id=1022901&p_id=1419&seq=1&format=2
plug it into your TV.

Buy this: http://www.monoprice.com/products/product.asp?c_id=104&cp_id=10423&cs_id=1042302&p_id=6884&seq=1&format=2
plug it into the optical cable

Buy this: http://www.monoprice.com/products/product.asp?c_id=102&cp_id=10218&cs_id=1021815&p_id=5612&seq=1&format=2
plug it into the adapter

Buy this: http://www.monoprice.com/products/product.asp?c_id=102&cp_id=10218&cs_id=1021802&p_id=644&seq=1&format=2
Plug one end into your Bose Wave radio and when you want TV sound manually plug it into the TV adapter, when you want music unplug from TV adapter and plug it into the Apple Express.

The manual switching part is not exactly ideal but with only one input on the radio you're kind of limited. You may be able to find some kind of 3.5mm A/B switch on that website but I'm sure it would be manual anyway.

There are manual A/B switches, but they run at least $25 and you still have to get up and flip a switch. The above solution should work fine, but be sure your TV can be set to output PCM, or that it only outputs PCM from connected devices. The DAC will only work with PCM input.