Yes, the speed of the scan is greatly influenced by your resting heart rate. I believe the estimated scan time is based on a resting heart rate of about 70, so if your resting rate is lower, the scan will take a bit longer.
The other aspect that slows a scan down is a data read error. For every data read error experienced, Spooky2 will require 3 consecutive good reads before it resumes. This has the potential to extend the time out a great deal.
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