In both my systems I use an simple aux rca input. Granted it's set up for that from get go. I can use the signal from any thing sending signals through rca's example DVD or game systems. I love the portability and the kids love using it. So if your head unit accepts input then why not.

 

if its got rca input(AUX) then a 2.5mm to rca cable will work
if the 2.5mm jack has aux and cal mic in the one socket then a 2.5mm to 2.5mm lead will work also

You will always lose audio but you won’t hear it.