Paul, Thanks for posting.
Olympe, thanks for helping.
We have had a long standing issue of having occasional sesion drops in strong signal conditions. This would depend upon the data traffic pattern and most susceptible to happen at 8X links. This has been addressed in release 20.0. The 20.0 Beta Release Notes read:
Improved Link Performance
A new encoding/decoding introduced in 20.0 improves the performance of the link in a variety of traffic payloads. It also decreases the likelihood of lower modulation or a dropped session due to a specific packet payload. For this reason, we recommend that SMs are upgraded first. If the AP is upgraded first, each link will run at a max of 2X MIMO-B until the SM side is also upgraded. As always, it is recommended that both sides of the link be running the same software version.
Would you mind being able to try the latest R20 beta and letting me know how the sessions are?
Another workaround in debugging could be to limit the max rate to 6X and monitoring the sessions. In R20 this will not be needed, can run at full 8X.