There is another topic regarding an upgrade to sensor version 5.8.
I took this upgrade today via Garmin Express.
Later on I did an indoor cycling workout with the Garmin ANT+ speed sensor and using on board HR.
For the first time I did a workout (33 minutes ling) without any dropouts.
For those with this ANT+/HR dropout issue, please take the upgrade and report back.
Hopefully you can have a workout that looks as clean as mine.
ciq.forums.garmin.com/.../1318902.png