You'll want to use the Audio OUT jack on the Television . . . Not the Audio IN jack. That way, you can switch your radio/DVD player input to "AUX 1" and play the television sound through the house speakers, in addition to the tv speakers. Unfortunately, I haven't figured out a way to play DVD sound through both the tv and house speakers. Hope that helps.
2013 Eagle 266RKS
2011 Ford F-150 w/3.5L Ecoboost & H.D. Tow Package