Hold down the Windows key and tap the Pause or Break key (and the FN key on some) for a shortcut to the system window which will tell you this. Or do the Windows key and "i" key and hit PCinfo .
If you want more shortcuts let me know (or see FR thread here
Note also that if you want a vast improvement on sound, for about 2.00 you can get an FM transmitter. I wonder why it is not USB powered though
Better to hear the word of God with.
I have a desktop where the sound output has become erratic. I bought one of these $2 USB devices to bypass it. I leave it unplugged most of the time
http://www.ebay.com/itm/USB-2-0-to-3D-AUDIO-SOUND-CARD-ADAPTER-VIRTUAL-5-1-ch-High-Quality-New-EN24H-/120987665271?pt=US_Sound_Card_External&hash=item1c2b6d4377