I have had great luck with Wahoo until now. The BlueSC is a combination cadence and speed sensor. Recently, it stopped sending speed. The sensor arm is correctly aligned. I recently replaced the battery and it worked for 90 minutes before failing to send speed again. And...without speed, I cannot get distance with the current setup.

1) Has this happened to anyone else?
2) Could the "new" battery be stale? I purchased a pack of them several years ago.
3) Could the magnet on the spokes be the issue?