Hello, any solution to problem? I am having similar issues with e90 -05 with DSC, radio cut off and sometimes power going off for a millisecond. E90 technichs are partly similar to X5. Alternator is overcharging and undercharging. I changed the voltage regulator and the problem seem to be solved for a while, charging was stabilized, but now it begun again. I have doughts that the alternator broke regulator again but seems like You are having similar problems after replacement of alternator?