Calls Node Skew Issues

[cpg178]

Starting having a problem out of the blue about a week ago where my node will go offline as the calls get rejected due to excessive skew. A few minutes later it will come back online with no issues. This happens once or twice a day usually in the middle of the night.
I have had the same setup for months and nothing has changed, the time is synced regularly back to the Windows time server. Any ideas on this besides going and manually syncing the time every day?