Hello, I have had my Venu 2 for a week. Every time I do a cardio workout, using the "cardio" setting, the heart rates are wildly off from this watch. I am using a Polar H10 chest strap to test against. When I do a typical cardio workout using a DVD routine, e.g. Cathe Friedrich cardio routines etc., I get ridiculously high heart rates from the Venu 2. For example, when the H10 said my heart rate was 123, the Garmin watch said it was 172. I have tested this multiple times and it always comes out like this. This goes on for the entire workout. I have carefully checked the watch fit every time, and I clean it as directed. I have read almost all of the 68 page Venu 2 user manual. Nothing has helped with this so far. The Venu 2 does seem to give me fairly accurate heart rates on the more mild workout types, e.g. I have tried walking, yoga and pilates, which are give pretty close to the H10 readings. What is wrong here with this cardio issue? Thank you in advance for any advice on how to solve this.