HTC One M8 not receiving calls?

[AC Question]

Okay, so I have had my HTC One M8 for a long time now for maybe a year and a half now, and (yes, it is rooted) running Android Revolution. Anyways, it was running root perfectly for a couple of months now but now I am not getting calls, it just goes straight to voicemail, but I can make calls and I can also send out text messages/use my mobile data. I took it to the AT&T store and they even gave me a new SIM card and it STILL didn't work! I am running out of options here... =/

 

[ShadyAleexx]

It's HD voice call. AT&T recently turned it on for every device and the roms don't support it. You can change from LTE to 3G though and you should receive calls. That's what I did, I read it somewhere and it's been working for me. I also saw that you can call AT&T and ask to get hd voice turned off for your line.