Yes we had seen his before - although from memory not in AC19 .
Here some questions to investigate further:
1. Does this happen to all users on all files, or only specific users / files?
2. Which App CHICAD 19 build are you on?
3. Which macOS are your workstations running on?
4. Which macOS is your file / bimserver on?
5. Is SMB disabled on your fileserver?
FWIW for the first time in a long time, we would recommend upgrading all AC19 Files to AC20, as GS seem to have fixed quite a few bugs that still were present on the latest AC19 build. We did a few already and did not encounter any problems so far.... fingers crossed.