Beware of 'Ghost Switching'

I have had a C-J Primier 17LS for over a decade and it has served me well. About a month ago it started switching from phono to C.D. or other modes, all by itself. I never had this problem before. I don't use the remote so took out the batteries thinking the remote may be the issue. No help. The Ghost Switching only occured while I was in the Phono Mode. I sent the unit back to C-J for repair. They had it for two months, could not replicate the issue and found nothing wrong internally. After I put the unit back in my system it started to Ghost Switch again. I placed a tin foil shield over the section where the romote sensor eye is located on a hunch. No more issues. It seems outside signals were causing my pre-amp to Ghost Switch. Not sure what type of signals could cause this, but if you experience such an issue save yourself some grief and money by placing a shield of heavy tin foil over your remote 'eye'. This may start to become a common issue with all the wireless devices in use.