I think I said already that my model is Xiaomi Redmi Pro 3 International Version.-kalos
Pick one and then tell us what version of MIUI it's running:
As I have previously said, identify it by its board name because as you can see, there is no
Redmi 3 Pro International Version.
The EU ROMs do remove a lot of the unnecessary Chinese stuff and add some extras geared towards non-China residents plus some system optimisations
BUT it requires you to unlock the bootloader and flash an alternative, ie. TWRP.
NOTE: If you've never done this before or aren't prepared to wear the consequences of doing it incorrectly then DON'T.I don't use MIUI at all, which I said previously, it was removed within 24 hours of getting the phone ... it sucks, it's crap, I hate it. I hope that makes it clear what I think of the MIUI OS. I didn't have any problems using it or the phone doing weird things, I just don't like it.
Having tried a few ROMs I now use CyanogenMod 12.1, (Android 5.1.1), with a few tweaks, any problems I had have pretty much gone. Another ROM gave me some features that CyanogenMod doesn't but Xposed + modules and/or apps have replicated them.
Assuming you're really talking about the
Kate version of the
RN3, there is a lot of good info in the Whirlpool forums:
https://forums.whirl...eplies.cfm?t=2566258https://forums.whirl...eplies.cfm?t=2603115https://forums.whirl...58&p=6&#r120 - A guide on flashing alternative ROMs on the RN3SE
It's mentioned that MIUI is rather aggressive regarding memory management which can cause it to force close apps, maybe that's the case here.
http://www.technocia...-miui78-secret-tips/https://www.reddit.c...6d93&sh=d0a0c711FWIW, I also turned off battery optimisation on a per app basis and it actually seemed to increase my battery life - go figure.
I have little doubt that flashing something like CyanogenMod or LineageOS would probably fix most issues you're having, (bearing in mind there is still the possibility that you just happen to receive a faulty phone - happens no matter what brand you choose).
Unless you're willing to undertake the necessary steps yourself, invalidating your warranty, and wearing any consequences of doing it wrong then in your case you're better off buying locally in a store.