Event/Failsafe = FAIL - ERR found: GPS Despite good GPS

Recently purchased a new APM 2.6 along with the Ublox-6M GPS/Compass combo.

Stabilize and ALT hold mode are perfect, however when I switch to LOITER It immediately flies off in a random direction.

When in MP it shows an excellent GPS lock and the position is correct.

I have verified compass calibration is correct via an external compass, everything is dead nutts.

LOG:
3509
Duration 21:13:19
Vehicletype ArduCopter
Firmware Version V3.2.1
Firmware Hash 36b405fb
Hardware Type
Free Mem 0
Skipped Lines 0

Test: Autotune = NA -
Test: Balance/Twist = NA -
Test: Brownout = GOOD -
Test: Compass = GOOD - No MAG data, unable to test mag_field interference

Test: Dupe Log Data = GOOD -
Test: Empty = GOOD -
Test: Event/Failsafe = FAIL - ERR found: GPS
Test: GPS = FAIL - Min satellites: 0, Max HDop: 2.18
Test: IMU Mismatch = UNKNOWN - No IMU log data
Test: Parameters = GOOD -
Test: PM = NA -
Test: Pitch/Roll = NA -
Test: Thrust = NA -
Test: VCC = GOOD -

Like I said, GPS is excellent in MP, even indoors.

I have GPS set on the Pre arm check and and im not getting any errors…

No diea…

Did you ever get this figured out? I have the same issue.