305 pacing incorrect

Just back from a 5 mile run and my garmin 305 said that i was running at 7.05mm.  

All other data seemed to be okay apart from the pace.

Any ideas - and even if my life depended on it I couldnt run that fast over 5 miles.

I have a 405 not a 305 so not sure, but...

What does the total time and total distance say?  If you work out your average pace from that what would it be?  Are you looking at something like 'maximum pace' or something?  Also, I'm sure on a gadget I had once, if you looked at the pace of the last part of a mile you did, it messed up the minute mile pace - so if you had done half a mile in 5 minutes, rather than saying 10mm pace it said 5mm...

Just some thoughts.

Or maybe it's just telling you to get a move on

If you look at a graph of what happened in your PC you can see what happened. My best guess is that you are looking at the average pace figure, and that has been corrupted by a false reading blip.

I once saw a blip on my trace that gave me a max speed for the run of something like 600 mph, this I assume being from reflections in a built-up area, or some kind of interference. If such a reading has gone into the averaged figure for pace, it could account for what you see.

Thanks for the replies.

This has now happened for the last two runs, but never in the 18 months Ive owned it.

Will download and see if things become clearer.