I think I've had a few of those too but suspect it's more on an older PC than new ones. My problem is more how long it takes to get Wu's to do. Seems like 2 hours: Get WU's, complete in a minute but waits an hour to upload, then waits an hour to download another set. Trick I've used is to upload them right a way manually, then I get new ones the next hour and then manually upload them again. I bit time consuming but I can do this a couple of times a day to get extra WU's. Which I could use the 64 core setup and grab a bunch at once. Definitely one of those tortoise projects and hurry up and wait.