I have a strange problem in my 528iA-98 the car has a original BMW bussines CD and Radio and sometimes rather frequently the speakers stopps working, this could happen with anyone but not the rear right speaker, all the others will failure some times, and then suddenly starts working again. The GSM speakers always works !. I dont know if they are the same as for the CD radio. The car has 12 speakers as original. I also want to know if there is any place where I can buy a workshop manual for the car or if its possible to find it on the internet? Please can anyone help me.