On and off GPS issues

[kentchristopher]

For awhile now I've had issues with the GPS on my i9192 where, using GPS Test, it will:

• See multiple satellites but not get a lock
• Seemingly "freeze" (satellite signal levels in GPS Test stop fluctuating)
• Sometimes work fine
• Sometimes only see 2 or 3 satellites despite being in a good location

These issues translate into GPS problems in my maps application (Here Maps), e.g. the maps app will be unable to get a lock, sometimes showing it has a lock for a second and then losing it again, which makes GPS navigation impossible.

I'm wondering if anyone else has experienced issues like this and whether they found any resolution, or whether anyone has any ideas as to what the cause might be.

I've tried:

• Resetting/updating the AGPS settings in GPS Test
• Editing gps.conf through FasterGPS
• Editing gps.conf manually with various settings (rebooting after each change just in case)
• Changing ROMs (from CM to LineageOS 14.1)

My feeling (and hope) is that it's a software issue since it seems to work better after a reboot (though not always). My next troubleshooting step will be to install a stock ROM and see if it resolves the issue, unless anyone else has a better idea. In particular I'm wondering if flashing a different modem/baseband would affect the GPS performance. Right now I'm on XXUCOA2.

Anyone have any thoughts?

 

[kentchristopher]

An update: After reverting to a stock ROM, GPS performance was vastly improved, with no sign of the troubles getting a lock as was the case with LineageOS 14.1 and the CM ROM I used before that. I'm now trying to go back to Lineage OS 14.1 to see if the flash of the stock ROM (and new baseband) may have fixed it, but initial tests using GPS Test suggest that the ability of the GPS to get a lock is not as good as stock (too early to tell if I'll have the same problems not getting a lock at all).