I reverted back from the latest version to _V9.1R31.bin.Sean My KHG gets weird readings sometimes too.... I dont have Apex... I can pull logs and show you its honestly bad.
When really I am at 8. I have it adjusted for -2 DKH. and finally just went with its going to read higher.
I have used this firmware without issue for years.
I'll let you know how it goes.