Fixed or freewheel Powertap? I assume you were actively punting power down when it was dropping?
Fixed, no significant change in power before or after dropouts.
Factory reset head unit and try again?
Might just be Garmin having mega-lolz with you. Hopefully.
@umop3pisdn started
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Fixed or freewheel Powertap? I assume you were actively punting power down when it was dropping?