Perhaps it could be a problem with spawn location? (If spawn point is set to be in a wall) I myself was unable to test this, but just voicing out a few thoughts.
If the spawn point is correct perhaps its more a issue of the job/lua/addon or maybe even with the whitelist system itself.
I suppose one thing you can do, is to verify game integrity for Gmod on Steam, in case there's corrupt/damaged files.
Steam Library
|_ - Gmod (Right click)
|_ - Properties
|_ - Installed files
|_ - Verify game integrity
