It looks like the most recent ELEMNT firmware update introduced an issue with SRM power meters. If you have one, and would like to try out a BETA firmware that should address the issue:
We do apologize for any inconvenience this might have caused. We narrowed down the issue to the SRM power meter and have a fix for it in our beta group. Anyone who wants to opt into that release and get an early fix send us an email qa@wahoofitness.com
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The issue with the SRM was with the autocalibration that they have in place, that was throwing our metrics way off. We only had a handful of users with other Power Meters experiencing issues and after a bit of troubleshooting it turned out the issue was with the Power Meter.