I'm using the 5630 as a USB modem, and every time I try to do something heavier (eg. youtube, downloading a file) the connection stops working after 10-20 seconds. It doesn't disconnect, but nothing gets through either.
This problem seems to exist only in Win7 and Vista, because in XP it works like it should, no problems whatsoever.
Solved! Go to Solution.
Turns out it was a problem with Windows' USB driver, this fixed it: