[Galaxy S 4 Q&A, Help & Troubleshooting] rsngfrce:
Thanks!

First of all, I seriously cannot express how grateful I am to you for your ATTEMPT to help me! I completely understand your knowledge of the Sprint version of my phone is limited, but you have already provided me MUCH more assistance than anyone in the Sprint specific forum. While I would love for someone to to tell me do "x" and then "y" and your phone will be fixed, when I came to THIS forum, I was only really hoping for general ideas that would help me think about my issue and you have certainly provided them! :highfive:

(IMPORTANT NOTE): When I 'dispute or disagree' with what you say in the following, I AM NOT SAYING YOU ARE INCORRECT IN ANY WAY, I am just expressing my PERSONAL current understanding of my situation, which I feel helps me to think these things through and might or might not make things clearer for you. I will also provide MUCH MORE information than I'm expecting YOU to think about or respond to, I'm really just recording it, which also assists ME thinking about it.

You are very much correct about it being a strange problem! What I find MOST STRANGE about is that it occurs at some point, usually at least about 12 hours after booting my phone. IF I never had a mobile connection and GPS, it would MUCH less strange. I recently helped another Sprint user who had installed a non-Sprint specific Google ROM (a mistake in the first place, no doubt) ►►[AOSP] Official 4.4.4 - S4 Google Edition - Stable-R2 - Feel the Experience of Nexus◄◄ which worked fine, but he had NO mobile connection. ROMs are CERTAINLY not my area of expertise, having only ever been stock-rooted, but I took it upon myself to assist this user because he was new and the KT-SGS4 kernel he was using with this ROM, I noticed, appeared to me to be the KitKat version, and I believed from the ROM that it should be the AOSP version. Had him flash the AOSP version of the kernel, which resulted in bootloops. Then I discovered that there are Google versions of the KT-SGS4 4.4.4 kernel for other carriers, but not for Sprint, which is the kernel he had in the first place, which comes with the ROM. Apparently, it all works fine on the Sprint phone, but unsurprisingly to me, you get no Sprint mobile connection. I was able to find a similar Sprint specific ROM, which he flashed and it completely solved his issues. But I digress...

Yes, I am running NAE with MF9 bootloader. This is because I started on MF9 without Knox. If I upgraded to the NAE bootloader, I would never be able to go back to MF9, because of Knox. Numerous people have told me Knox does not matter because I am out of warranty anyway, however I PREFER to have the option to go back to MF9 if I should need to, which is why I upgraded in this way. I followed an established upgrade path to achieve this and have seen nobody else who has has used that upgrade method develop this issue.

I think this is probably the best suggestion I have received so far. I have NEVER not used a stock rooted ROM, because my main desire is stability and that is where I have believed I would find it. However, I think it is time for me to investigate a custom ROM, at least try one, and I have posted a thread in the Sprint forum for recommendations (and I'll certainly do some research myself). You are really pushing me in a direction that I NEED TO BE PUSHED because it is obviously a direction I need to go but have been avoiding, for some reason. Either custom ROM, or even back to MF9 and then upgrading again. I'm not sure WHY I haven't tried it yet. Honestly, assuming the issue goes away, I hate the idea of SLOWLY adding things back in until the issue occurs again (IF it does)... I don't know if I am to impatient for that or what it is. I don't know if I am impatient if I can deal with having a phone that continually looses the mobile connection and GPS for two months, so its a bit of a contradiction! :silly:

I'm actually a bit familiar with the modem issues on your phones from attempting to help a user in this thread: [REF] GALAXY S4 (I9500/I9505) GSM / NON-HLOS - MODEM'S Collection (Odin/CWM/TWRP) who was getting the unhelpful "read the op" replies (in a circle) which WHERE NOT answering his question! But these issues do not exist on the Sprint version. I COULD try going back to a modem version prior to NAE, but SINCE the NAE modem WAS working in the beginning all the time and because it works FOR A WHILE now, I don't see that being the problem.

So, as it stands, my next step seems likely to be a ROM flash. I'm grateful for all your time and assistance! :good: