I recently changed from Solar instinct 1 (no problems whatsoever), to Solar instinct solar 2, which has been giving me some issues. On hard activities, and while using a chest strap the HR is all over the place, one minute I'm in Zone 4, the next I'm in .08. It makes it very hard to see whats going on training wise. In reviewing some of these posts it might possibly be the OHR sensor is off? Has anyone had similar issues while wearing a chest strap? I was going to swap to another strap to see if that is it but wanted to ask first. As an example yesterdays run would go from zone 4 to zone 1, then jump to 3, then no reading, then back to 4, it just kept going all over the place. Around half way through the run I took off the chest strap thinking it must have gotten water into to it or something, and it was even worse, no reading to a high of 1.1. I stopped cleaned the back of the sensor off, and dried my wrist (wearing on left), and still nothing. I've heard that wearing it under your wrist might help, but I dislike that idea.