Old thread, but since I ran into this issue and had to find a fix and this post is the top of google here is how to fix it:

You have to disable ULPS (ultra low power saving feature):

1) Click Start - Type regedit.exe and hit enter.
2) In reg editor, press F3 and type EnableULPS, hit enter.

3) Keep pressing F3 until it finds a key called EnableUlps in a sub folder called 0000
4) Double click the reg entry and change value from 1 to 0.

5) Keep pressing F3 until it finds a key called EnableUlps in a sub folder called 0001
6) Double click the reg entry and change value from 1 to 0.