Giant ridesense issues

Deleted original thread as thought I'd fixed it by replacing battery, but no.

I've had a Giant Ridesense speed/cadence sensor on my propel running fine for 2 months - then all of sudden it's started to constantly flash red/green, even when stationary.

Removing battery for ten seconds resets it. It will then detect the wheel magnet and crank magnet separately for a few revs but then looks to flip out and just constantly flashes again until the battery is pulled out.

Anyone had similar issues with this sensor?