Time differences: total/moving time

[Lenz]

Hello,

I've been using Oruxmaps for a few years mainly for orientation purposes and sometimes for track recording. Now I tried to use it for training purposes and two questions came up:

1) Although I was walking/running without pausing total and moving time differ quite a lot (6 to 10 minutes on a 1:15 hour track).
2) I used the follow route function and "delay in route" in the dashboard. While "delay in route" showed I was in the lead (9:17 and 10:31 minutes on my last two attempts) when I arrived, neither my total time (-4:43 and -4:45) nor my moving time (-0:29 and -5:42 minutes) are close to this time advantage.

Do I misunderstand something or could there be a problem with my GPS (settings in the GPS section: min. time 2 sec. / min. distance 5 m / accuracy for position fix 50 m)?
OruxMaps 8.2.0 beta 23
Phone: Xiaomi Redmi 4X with MIUI Global 11.0.2 (I know it's a bit outdated but up to now it meets my needs ... and it's not of the size of a small tablet pc)

Thanks in advance
Lenz