First, I noticed that the left pedal has gotten quite stiff. It doesn't turn at all when I rotate the cranks, but when I'm riding, I don't really notice a difference. I looked at Garmin Support, and saw that there is a video for doing pedal maintenance. I'm taking the bike to my shop tomorrow to get the pedals "overhauled" by someone who knows what he's doing.
Then, about the last three or four rides I did on that bike, I noticed that the pedals keep dropping and getting found again. Irritating! I removed the batteries for roughly 15 minutes, swapped them side to side, and reinstalled them. I haven't had a chance to ride and see whether the problem is still present. The batteries have under 43 hours use, and I haven't seen a low battery warning yet. The last two sets of batteries I used lasted 72 and 53 hours. I am up to date on software.
Is there more I should do to troubleshoot this problem?