FrSky GPS Specific Telemetry Error

Cube 2.1, AC 3.6.10, FrSky X8R and Horus X10S OpenTx 2.2.3
Telem2 is configured to output FrSky smart port telemetry with option 4, DIY adapter.

All other telemetry values work great, except I am getting GPS telemetry errors every few seconds on my X10S. I seem to remember a OpenTx post at some point in time where the author blamed the Arducopter implementation for the FrSky output.

Is anyone else having this issue are can suggest a solution?