Code sometimes freezes when accessing netref objects

[Verpous]

At my work we're using rpyc, and sometimes when accessing a remote object, the code freezes. There's no consistent pattern to when it happens or on what line, but the stack trace always looks something like this (particularly line 121 in poll):

  File "/usr/lib/python3.6/site-packages/rpyc/lib/compat.py", line 121 in poll
  File "/usr/lib/python3.6/site-packages/rpyc/core/stream.py", line 46 in poll
  File "/usr/lib/python3.6/site-packages/rpyc/core/channel.py", line 47 in poll
  File "/usr/lib/python3.6/site-packages/rpyc/core/protocol.py", line 382 in serve
  File "/usr/lib/python3.6/site-packages/rpyc/core/async_.py", line 47 in wait
  File "/usr/lib/python3.6/site-packages/rpyc/core/async_.py", line 100 in value
  File "/usr/lib/python3.6/site-packages/rpyc/core/protocol.py", line 469 in sync_request
  File "/usr/lib/python3.6/site-packages/rpyc/core/netref.py", line 76 in syncreq
  File "/usr/lib/python3.6/site-packages/rpyc/core/netref.py", line 161 in __getattribute__

Environment

• rpyc version: 5.0.1
• python version: 3.6.15
• operating system: linux

I know the version is a little out of date but it's not possible for us to update it due to the constraints of working in a large corporate environment. We're in a difficult position where we have to do something about this issue, but our hands are somewhat tied. Also because we don't fully understand the issue, there's no minimal example. I guess my hope is that either someone can recognize this bug from the trace, or that someone might help us figure out if we've set up something wrong. Thanks.