Mine occurred on my Rack with remote, was primarily in Performance 1 Slot 3 (it's a simple mid gain Marshall profile). I have a Mission EP for volume boost (used only to boost for solos) and a Mission EP for wah (which gets infrequent use because, well, it's a wah). Neither was being used in my case. The signal cut-out was intermittent, would last several seconds, then restore, then do it again. Seemed very random (not on a time cycle nor related to whether I playing hard or soft, guitar volume at 10 or less, etc.). I checked every connection between the guitar and the Profiler, the remote, etc. Nothing about the displays (on the Profiler or Remote) changed when this happened. The signal cut out on the connection to the mixing board and to my monitor. Teh cut out happened frequently and was very noticeable during any songs. Rebooted the Profiler several times but no joy.
I'm downgrading to 8.7.10 today. Berkhard very nicely sent me the prior OS by email when I contacted Kemper (great service). I don't think 8.7.10 was available on the Support|Downloads page last Thursday (see my post above). I wonder if Kemper are getting a lot of requests to downgrade.
The Profiler is a complex piece of equipment, and if there's any kind of glitch in the new OS that's certainly no deal breaker as long as the user can easily reinstall the prior OS. Kemper was very quick to respond my email and support my request, which is fantastic customer support not seen with many companies.