I have had this happen twice. The first time I though it was just "a glitch" and rebooted the app and it corrected itself. However, it's happened a second time this morning.
So I'm flying along and the inner ring was showing about 5-6nm. The outer ring, about twice the sitance out should show 11-12nm, but it showed (the forst time) about 34nm, and, this morning, about 66nm. I have the rings set to dynamic. However, as I said, the forst time, I rebooted and the outer ring then showed 11nm correctly.
Because it's now happened twice, I believe it's a bug.