Help!!! No sound!!! Sometimes??

[Dvldogyut]

Ok first off I have a kenwood ddx-514 in my 2001 tahoe. Sometimes when I start my tahoe the radio and radar detector cone as soon as I left off the key. Other times my radar detector doesn't come on, and my hu powers up and shows that it is playing, you can change tracks, put in a DVD and the video play but no sound at all on anything. Cut it back off and it might start playing music and it might not. Any ideas what my problem might be?

 

[blueflamed03]

retrace your power connection.

 

[NASHTIME]

check every wire and see if its loose