the time that it is sent is determined by the last number in the CWOP ID number
for your case, that is 1 (e.g 10:01, 10:11, 10:21 etc)
what speed PC?
how much memory on the PC?
if you have WD set to do lots on the 10 minute (10:00, 10:10, 10:20, etc) then try unsetting that as a test