My TomTom Runner often shows the wrong speed, as compared to others that I run with. Usually my speed is lower (too slow)
This morning I was in my boat at a steady pace of about 11 km/h. I was wearing my Runner, so I decided to check my speed.
Every second or so the speed fluctuated strongly, betreen 5:15 and 6:50 min/km, and quite often no speed was shown also.
About a month ago I noticed that when running around a particular block many times, at a pretty constant speed, while going N-S the speed was much higher then when going S-N, at least at 5 occasions..
When uploading the data, the numbers seem to be correct (both speed and distance).
Any suggestion what might be wrong?