Yes have been to my dealer with the problem and he would have put a new radio, but then they saw that radio is not covered by extended warranty, damned!
So they contacted service as well, but haven't heard back from them. They said it worked fine, but next time I get there I'll SHOW them.
And for the temperature thingie, I noticed that the internal computer in general works very slow when its colder (try to switch from milage to avg speed to ... on dash, you'll see it lag when it's very cold) So here's the theorie: when it's colder the computer works slower and can't handle the processing of the music, and certainly not high bitrate mp3s. Whenever the light on my usb drive stops flashing (meaning it's not reading anymore) then you know it will freeze within 10 sec or so. Or when you skip a song when it's stops flashing: same thing. So it crashes, stops filling buffer, can't restore connection and freezes when buffer empties or song is skipped.
Any other news from anyone else yet?