I have been experiencing conflicting max hr readings between my forerunner 235 and Garmin connect after I run. After I run I sync with GC and Max hr on forerunner not same as on Garmin connect after syncing. Forerunner seems to be pretty accurate and Garmin connect is 10-15 beats higher. Kind of strange GC would not be the same as the Forerunner reading. Any suggestions to get these 2 in sync?