What is really worrying, instead, was the report GSX crashed on landing (or likely before). This shouldn't happen, but if it did, an automatic restart will likely cause stuttering, because during a restart there's lots of file access required, so we should probably verify if this was the case.
Checking the auto-restarter log at %APPDATA%\Virtuali\couatl64_boot.log file might tell if there was a restart on (or moments before) landing, since it comes with timestamps.
Unfortunately, i had done two more flights after the one where Couatl64 crashed, so the couatl64_boot.log file is only showing the most recent flight, where i didn't encounter a crash (just the freeze on landing though it wasn't very long on that flight). There is nothing in there between the messages at 1:02am when i started the sim to 2:57am when i was already at the gate at my arrival (might even be when i exited the sim). If it happens to crash again at landing though, i will be sure to note the time and grab that info out of there.
I had this issue also and is gone on 3.5.6. However I only noticed it on PMDG planes....3.5.8 didnt give the pause when using the Fenix A320. Can everyone clarify they were using a PMDG product? I used the 737-700/800 when getting the freeze.
I have had the freeze with the Fenix A320. To date, i've had it with the Fenix A320, FSS E170/175, iFly 737-MAX8, and the PMDG 737-700/800/900. The length of the freeze has been varying though, anywhere from barely a second to now up to like 10 seconds... I have not tried to roll back to GSX v3.5.6, but i have found, like others here discovered, that changing all services to "0" except for the jetway did clear up the issue
completely on the only plane i ended up trying it on (PMDG 737-900). I have no idea about why the length of the freeze varies though; however if Yoda_1976 determined the TLOD can affect the length of the freeze, maybe it has to do with what is visible of the airport at touchdown? That's just a guess though.
Unfortunately, might be a couple of days before i can get back to MSFS, so i won't have anything more to add to this for a bit.