Bad tag subscription on Vision client


Having problems with bad tag subscriptions on our vision client.
The picture below shows the problem:

Diagnistic window for the current client:

This problem occurs daily, with irregular intervals. Sometimes it could be solved by switching windows, but often the client needs to be closed and opened again.

Could it be a timeout problem or something with the subscription update on the PLC reading/writing the tags? The number of tags affected varies.

The timeout suggests something bad is happening on the gateway at that time. Is there anything in the gateway log that shows up at the same time as these failures?