Where to hook up a telephone mute wire on a lanzar SDBT75N deck

SOURCE: VRX755VD "triggered audio mute for cellular telephones"

Well, it sounds like you need a new output IC, which is what produces sound to the speakers.

SOURCE: lanzar model SD43MU(( dvd/cd player wont work not funtions for that wont even appear?

I have a similar Lanzar unit. I had it in twice while it was under warentee for the same issue. I also had it in a couple more times for other issues. It cost me about $30 shipping both ways each time I returened it. About a month after the warentee expired, the DVD quit ejecting again.

Bottom line, I would look at purchasing a different uint or use an ipod instead of the CD.