GPS altitude issue since rooting

[DarkBeer]

Not having any luck over at XDA with this question, so figured I'd try the helpful folks here. I use Endomondo to track my mileage on bike riding. Since rooting and moving to ViperDNA, I am having an issue with inaccurate altitude readings. The distance is still measured accurately, but I live in the flatlands of Indiana, and my tracks now look like I'm riding in hilly country, which I am not. The only suggestions I have received so far have been to turn off all of the location settings, reboot, then turn them back on, and to use a GPS status app and redownload the AGPS data. I have done both of these things, but it hasn't helped the issue. Since this same hardware worked fine when non-rooted, I have a hard time believing it is anything other than the software. I haven't tried another ROM yet, so may try that over the weekend. Just curious if anyone else has run into a similar situation and was able to resolve it? Below are two screenshots of identical rides. First one is when I was still stock, and second is after rooting and installing ViperDNA. Thanks for any suggestions!

The grey line represents altitude, the green line is speed. Notice that on the first chart, the overall scale for elevation ranges from 780'-840', but on the second one it ranges from 300'-900'

 

[Daniel.Lynch]

Not having any luck over at XDA with this question, so figured I'd try the helpful folks here. I use Endomondo to track my mileage on bike riding. Since rooting and moving to ViperDNA, I am having an issue with inaccurate altitude readings. The distance is still measured accurately, but I live in the flatlands of Indiana, and my tracks now look like I'm riding in hilly country, which I am not. The only suggestions I have received so far have been to turn off all of the location settings, reboot, then turn them back on, and to use a GPS status app and redownload the AGPS data. I have done both of these things, but it hasn't helped the issue. Since this same hardware worked fine when non-rooted, I have a hard time believing it is anything other than the software. I haven't tried another ROM yet, so may try that over the weekend. Just curious if anyone else has run into a similar situation and was able to resolve it? Below are two screenshots of identical rides. First one is when I was still stock, and second is after rooting and installing ViperDNA. Thanks for any suggestions!

The grey line represents altitude, the green line is speed. Notice that on the first chart, the overall scale for elevation ranges from 780'-840', but on the second one it ranges from 300'-900'

http://dolbeer.com/pictures/stock.JPG
http://dolbeer.com/pictures/viper.JPG

This is far beyond me. Have you tried posting in the ViperDNA thread about it? I'm sure if this is known by the devs they're working on it, or they'd like to know about it.

 

[DarkBeer]

Yes, that is why my post started with "Not having any luck over at XDA with this question..." I have posted it twice in the ViperDNA thread.

 

[Daniel.Lynch]

Yes, that is why my post started with "Not having any luck over at XDA with this question..." I have posted it twice in the ViperDNA thread.

Sorry, I was just asking whether or not you posted directly in the Viper thread.

 

[jasoraso]

My guess is you have a "kernel" that is doing some power management, which is affecting the GPS. Try a different kernel that is compatible with the ROM and see if you get any different results.

I'm on a Sense 5 rom (NOS) and use crpalmer's kernel, GPS for me is great on Runkeeper.

 

[DarkBeer]

I started with the stock kernel that came with ViperDNA, then switched to crpalmer's kernel. Same results with both. If it was power management, I would think my lines in the maps would also show me straying from the roads, which it does not. It seems to have good control over X and Y axis changes, but not Z. The distances on my rides are accurate, but the elevation isn't. The only thing that really throws off is the calculated calorie burn. I'm getting credit for lots of climbs that I'm not actually making
I think I'm just going to have to find time to try another ROM and see if it goes away, but everything else has been working so well that I was hoping to find a way to fix this one issue.

 

[RLGL1]

Altitude and GPS don't mix. It can be way off. The last time I looked at altitude, it was off by 100 feet