is this run in town / in the middle of tall buildings etc? it may be that the signal was reflected off the buildings, causing the error.
I could be wrong, but try uploading to motionbased.com - I think this autocorrects distance and elevation issues caused by 'random' signals, so could help in these situations.
new to the site, but just found this thread, so hope you don;t mind me adding to it.
Basically to get an initial signal it seems to help if the forerunner is as still as possible. i just put it on the ground next to me while i tie my shoelaces or something and don't seem to have a problem.
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andy silver
