I split this topic off from the GMod beta / ULib update topic
1) One person has it, one person doesn't, USUALLY means someone is running old code or conflicting addon.
2) For starters, for any new Gmod update, major or otherwise, we only attempt to 100% fully support sandbox.
Once we get Sandbox 100% supported/working, then, and only then, may we consider supporting other popular game modes.
We don't do #2 NOT because we don't like gamemodes, we do #2 because gamemode authors time and time again have re-written standard Gmod functions, or overridden them, that cause ULib/ULX to act in ways difficult to troubleshoot. Besides that, several incorporate their own admin functions, that often conflict on their own right.
I run 2 servers and it does the same thing on both. I'm running on a windows box.
That doesn't mean your running the exact same latest updated versions of all required files (TTT/GM13/ULib), or, may be running a conflicting addon that gaz492 isn't.
Most likely not a ULib issue.