AeroPod, PowerPod and Newton

The Newton worked fine yesterday, but today it went insane. First cold morning for the Newton this year, about 33 at start, it was indoors until the ride start. The first 3 miles look spot on, both in real time and in Isaac, similar to all my other rides. At that point, a stop light and first stop, I switch the display to"Enviro" to watch the time because I was trying to get to a point at about 10 miles to join a ride that goes by there at a certain time every Sat. and needed to watch the time to make sure I'd be on time. So I didn't see if the Newton was posting crazy numbers from 3 miles to about 14 miles (real miles, not what is shown on Issac) when I went back to the power screen. But here's what's way off: 1) it was a 24 mile ride, not 19.3 as Isaac says 2) the onscreen slope and wind numbers, after mile 14, were all over the map, jumping around from -5% slope to +7 to whatever, and wind numbers going form 0 to 20 to 13 to "xx" in a second some times 3) even when the wind and slope numbers weren't bouncing they were unconnected to reality, slope in particular often showing I was going down when in fact I was going up 4) the speed readout was all over the map as well and as a result the power numbers.

The profile is correct for the bike, the battery was at 100% at start, the wind cal showed 0 and the altitude at start was set correctly. The one screwy thing in the first 3 miles is that the elevation screen in Isaac shows braking before mile 3, there wasn't any, not once. Is Newton cold sensitive? Any ideas?

Ride file attached, thanks,

Not everything is the Newton's fault...

Your speed sensor was dying...you will see numerous dropouts starting around mile 5.

Replace the battery of your sensor and I suspect all will be well.

Hi John, I replaced the battery before today's ride, and did a data reset, but had the same problems: wildly fluctuating slope and wind readings, incorrect speed readings, along with the mileage being lower than actual. I can understand speed and distance being off if the spd/cad sensor is failing but why would that effect what the Newton reports for slope and wind, which were the most obvious errors?
Thanks,

You're likely using a Garmin GSC-10. In our experience this is a sensor that fails over time. You should get the magnet-less version sensors, and place the speed sensor on the front wheel. This will fix your problem.

We use speed, slope, wind, and elevation sensor data together. If one of those sensors is working improperly, it will affect the results reported by the other sensors.

Yes, it's a Garmin combined spd and cad sensor. I'll replace. Sounds like you're recommending separate spd and cad sensors, which would you recommend?
Thanks,

Garmin or Wahoo magnet-less sensors will work just fine. Attach the speed sensor to the front hub.