Have the same problem here with WinDV.  Running Windows 10 and a Dell laptop.  I have re-starting WinDV, sometimes the problem is corrected, other times I have re-inserted the ThumbDV, and other times I have done both with no luck.  I have deleted and reinstalled WinDV, no change.

I do not know if this is related, but I have another problem with WinDV or the ThumbDV where the incoming signal is unreadable. The incoming audio breaks up, words are cut in half.
 
Thanks for reading
Phil
W6PD