Poor treadmill walking results

This watch has always been terrible on indoor or treadmill (i.e. w/o GPS) walks. I've entered a correct stride length and generally walk at about 2100 steps/mile. So during an easy walk on the treadmill this morning it was telling me that I was walking at a 22 min/mile pace, which was reasonable accurate, but lagged well behind on distance compared to what the TM was showing. So at the end I had walked for 30 minutes at that pace and done 3100 steps, but it only gave me credit for walking 0.9 miles. The math certainly doesn't add up! Looking at what ended up on Garmin Connect, it recalculated my pace as more like 47 min/mile.

Anyone else seen results like this?