I recently added a number of additional domains to my AD Audit installation bringing my total to 6. Most are working fine, however on 2 domains I am getting RPC 6ba failures on some DC's.
Both of the affected domains are root domains with very little activity on them, as such I have 1 DC set to real-time collection and the remaining DC's set to scheduled fetch every 2 hours. The DC's set to scheduled fetch are constantly reporting RPC 6ba errors. If I set the failing DC's to real-time collection they work most of the time, but do still occasionally produce RPC 6ba errors.
Firewall rules are identical across all the DC's and the logs show no denies.