When playing a DVD on my XMS 1050 player, I get a annoying hum on all 5 speakers as well as the subwoofer. But when I change the audio out of the DVDplayer to SPDIF/PCM from SPDIF/RAW and listen to it in Dolby pro logic mode, there is no hum. The power cord is only two pins, and I have even plugged the reciver/subwoofer into another wall outlet. I do not have cable tv. The reciver/subwoofer is a Sansui SHT-12. Any help would be appreciated.