Ever since I installed the Avic X950 it has a whine coming through the speakers when it first boots up after that it goes away is this normal or is there something wrong with the unit. 

My X950BH has some speaker whine now and then and I think it is from the car's electrical system? Happens only once a month or less but usually when it is raining and since I am in So Cal that is not too bad. Anyways with yours does it make the noise when the key is on and engine off and the splash screen showing? Or does it happen only with engine running? If it is engine off it could be electrical interference from wires that have gotten wrapped around speaker wires or a unit problem. Did you have to install an adapter to mate with the car's electrical computer and that could be the issue also.

I hear it with engine off and key on and notice it the most when it is booting up and at splash screen. I am not using the speaker output from HU it is all hooked up with the pre amp outs. Seems to be only coming through the front speakers and not rears. Have tried different amp to rule that out and never had the problem before I switched out my Kenwood to the Pioneer. Trying to get a hold of there tech support and if it cant be resolved I will return it and go to a Alpine

Did you connect the cables as per pages 14 and 15 in the manual? With mine, in my Chevy HHR, I used an adapter and hooked the front speakers and rear speakers as per the manual but the rear preamp got hooked through the adapter box. I did not do that initially and did not get any sound?

It is hooked up correctly and I get sound it is just the annoying whine when it first boots up that I can not stand.Once it boots up the whine stops