I'm using Redmi 1S, and this applies to no matter what developper version (I've 5.9.17 now).
After changing MIUI V5 to MIUI V6, an error appeared when making calls in the car using bluetooth.
When on MIUI V5 the name of the telephony provider (i.e.: Movistar) appeared on the screen, on MIUI V6 only the numeric code instead of the name appeared (i.e.: 21407).
After that, with MIUI V7, none of the two appears. In this case is (none). See image.
Could this anytime be solved?