1040 faulty autopause/gps loss of signal

purchased one recently , 3rd time using yesterday & i had this very same issue!

Do you have a cadence sensor? I haven't had an issue since i disabled this. I'm bummed cause i like cadence.

That was a good find, thank you! I had this issue first time today, when using the 1040 on an older bike still having the old GSC-10 speed/cadence combo sensor. I never had any issue with cadence sent from a Quarq powermeter to the 1040 or from any cadence sensor to any other edge head unit. Which cadence sensor did you use? 

The plot thickens! Mine 10+ year old Garmin speed/cadence combo. I should try one from this decade to see if this works. Thanks much for posting this.

Interesting. I had the same issue my last two rides. The strange part is that it occured nearly on the same spot in both rides on two totally different routes (except the "faulty" spot). I'm also using a speed sensor. I could not get the device to work again until I restarted.

Do you also use the GSC-10 combo sensor or the newer speed sensor on the hub? That „faulty“ spot, was that the one spot on both rides with the densest foliage above or some other potential GPS signal obstruction? 

No, I'm using a cheap Magene sensor. I rode this "faulty" spot often with my previous Wahoo Bolt and never had any issues. While the spot is surrounded by trees (wide street through the forest) there's always clear sight to the sky. It's a long road with similiar conditions and I had this issue only on one spot.

I attached a picture of the route - blue line is part of the route, orange line is where the problem roughly happened.

Edit: I also have to mention, that I didn't stop the ride before the problem happened, so no Auto Pause occured. I was in full speed, and suddenly the display showed the pause sign.

In that situation and based on the information you gave, it is still physically possible that the issue you saw was lost speed sensor signal. I don‘t know the Magene - is it possible that the battery is dead or a magnet was misaligned? I also don‘t know that specific part of the „Steggerleswald“, but the parts I know are all tall trees. GPS needs at least four visible satellites, ideally as distant from each other across the sky as possible, and these may not always be available in the part of the sky you see on these roads. GPS may struggle to have good reception on the straights and have to struggle just that bit too much in the curve for a few seconds until it re-acquired some satellites to make a new fix. That wouldn‘t be a Garmin vs. Wahoo issue, afaik neither of them make their own GPS chips, so you could have that issue with devices from any manufacturer. In this theory, the Wahoo might have had help from a working speed sensor. At least, all of us have something to check. 

For what I saw yesterday, I can rule out battery issues in my case - the sensor sent cadence. Missing speed signal from a speed-only sensor is harder to notice since the edge will then use GPS to display speed.