I flew today and after about 10 minutes I noticed the rear lights suddenly go solid red for maybe 10 seconds then back to the normal green flashing with a red every once in awhile (9 satellites/NAZA mode). Has anyone else experienced this or know what it means?

pg. 48 of manual...
Solid Red is Error*.".......Red green and depending how many reds followed by green is indication of low number of Sat's GPS.
Should plug into Phantom Vision Assistant and see if your IMU etc. are all within spec!
Have you had a bad landing at all? Maybe something is jarred...
Are you on iOS or Android? Any issues with communications otherwise?

On iOS. I updated the Phantom app last week but haven't updated iOS software, maybe that has something to do with it. I can also tell you I was having a problem before flight connecting to the Phantom's wifi, it broke connection a couple times before staying connected.

cayers13@gmail. Posted at 2015-3-31 01:58
On iOS. I updated the Phantom app last week but haven't updated iOS software, maybe that has somethi ...

I would definitely ensure as a minimum the vision app is updated and it would not hurt to update the main iOS also, they usually go hand in hand!..."usually"..as the developers write or adjust code to go with the new iOS etc..

When I got my MCU error the rear lights were solid red, but it displayed an error on the app screen.

JATO Posted at 2015-3-31 02:22
When I got my MCU error the rear lights were solid red, but it displayed an error on the app screen. ...

I just saw your thread, sounds like the same thing happened to me. Also after upgrading the firmware :\

No error messages when connected to the Phantom desktop app. Guess I'll open up the shell and make sure nothing is loose.

As for the Green/red, since I updated mine if I only have 6 sats (showing on the app as 6 sats in green) I also get a green/red, it only goes green when I get 7 sats, never had that with the old firmware.

I noticed  that too. I amslowly leaning toward it may be an issue with the new the 3.12 firmware.

crash1sttime Posted at 2015-3-31 04:16
As for the Green/red, since I updated mine if I only have 6 sats (showing on the app as 6 sats in gr ...

That is in the updated manual, when 7 sats , light is green, 6 sats you get 1 red.

So presumably if you are flying and coverages is changing between 6/7 Sat's constantly the light sequences will Chang/be intermittent so to speak...

color codes

So 6 sats used to be ok but now DJI says it's not ?

crash1sttime Posted at 2015-3-31 19:45
So 6 sats used to be ok but now DJI says it's not ?

6 sats will keep your home point locked.  I think it is just a warning you are getting close to the minimum for sat lock.

I connected to the desktop app a few times, no errors. Opened the shell and examined everything, no loose connections anywhere. Gonna fly this morning but I'm thinking JATO is right about it being a 3.12 firmware issue. Hopefully just a glitch though and I won't regret updating