I received an iSport GT FW 4.21 3rd August. On the first day I did the installation and calibration ride/coast downs but only after I changed the battery in the wireless mount and the head unit (even though the included CR2032 was notionally brand new). The issue I was having was that it was resetting itself continually. It would reset over relatively minor bumps and often when I used the front panel button.
The battery also read very low after a short period (2 hours). I left it overnight and went out for a planned ride with my training buddy. The reset problem returned. The screen would fill with what looked like a boot sequence rather than the wind cal when it was behaving and it read 'data setup'. I assumed this is much like a hard reset (yup, the battery was in the right way up).
I had read that in some (older) units the battery in the head unit may not be pushed down enough and a slip of cardboard could be inserted on the top of the battery to cure it. I also had spares on me so put in yet more batteries and a slip of cardboard. This made matters worse. The unit, whether locked on the wireless mount or not, continually reset. We popped the battery lid and removed the cardboard slip and battery. It was at this point my training buddy noted circuit board under the Y shaped bottom contact for the battery and the fairly hunky padding on the battery lid. He suggested the issue may be the battery connector was shorting out on the lower circuit by being pushed down too much. It seemed to fit the behaviour; a bit of a bump and it may well have been shorting.
We took another thin piece of cardboard, placed it under the Y connector to insulate it and popped the battery back in place.
Bingo. Unit switches on. No resets and all looks well. It had behaved for a period the previous day so there was nothing for it but to try it on the ride.
A 100km ride, with gusty wind and heavy rain, rough country lane descents with plenty of hard knocks, and it was fine. When I got home I mailed the Garmin file from the 705 over to my buddy who had been keen to see how the iBike worked in the field and the resulting data. Looked great in WKO with no spikes and more than reasonable power numbers. Even with this issue, it looks like the iBike guys may well have another customer.
At home I popped the head unit battery cover and tried out all the other batteries and not only did each work fine but there were no resets and they showed good voltage.
So it seems there may be an issue with insulating the bottom Y connector to the CR2032 from the circuit board underneath. I say 'may' as there is a chance we fluked a fix but it doesn't look likely. I think a disk of insulation would seem to do the trick.
I've also read about some people having issues with shortened battery life and wonder if this is related as some kind of short may well drain the head battery. It occurs to me a similar insulation in the wireless mount may well be worth while as well.
Anyway, hope this is the end of it as, being in the UK, a return after 2 days to the US would have been a major pain. If the techs at iBike can confirm this may well have been the problem and solution then that would be great for peace of mind.