Two months ago, a friend asked me to install a multilanguage ROM in his brand new Xiaomi MI3 WCDMA device, since he is not fluent in English. Since then, the device exhibits sudden restart problems, even after factory resetting the phone and clean installing any multilanguage ROM. At first, I flashed the official stable fastboot image Mi3 WCDMA JXDCNBD14.0 (4.3), then updated to multilanguage KitKat 4.5.9 / 4.5.16 / 4.5.23 / 4.5.30 and had serious sudden restarts several times a day. I repeated the whole flashing procedure several times, always having the same result. After this unacceptable behaviour, I flashed the official developer fastboot image Mi3 WCDMA 4.5.30 (4.4), then updated to multilanguage KitKat 4.5.30 / 4.6.6 / 4.6.13 / 4.6.20 / 4.6.27 and now the sudden restarts are still appearing but only about twice a week. Is it possible for the multilanguage ROMs to exhibit such behaviour, in conjunction with some particular stable/developer base? Could multilanguage Xiaomi MI3 WCDMA ROMs need a specific developer base instead of a stable one? Sadly, I never thoroughly tested the phone using the official stable Chinese/English ROM, so it can simply be some weird incompatibility, or the phone can indeed have some sort of defective hardware. Since my friend is currently using the device, it will be difficult to reinstall the official stable Chinese/English ROM for further testing. As you can understand, if it is a minor hardware problem, it will be very difficult to try to send the device back to China, especially if the sudden restart problem appears only twice a week, since it could be hard to be diagnosed.