[Issey Miyake]

Had this problem 1 week after buying it. Swapped the phone with another HTC One M8 and worked for about 20 days. Same issues again. Cannot call out or receive calls, if i do the call will be dropped shortly after. Beyond frustrated with this issue. I've read about the LTE and spark issues on sprint w this phone. Best Buy and sprint keep saying this isn't a known issue. Switching to CDMA worked great for 1 whole day. My 14 day return policy is up at Best Buy so I'm stuck with this phone....What do i do now?

[mfreeland]

Had this problem 1 week after buying it. Swapped the phone with another HTC One M8 and worked for about 20 days. Same issues again. Cannot call out or receive calls, if i do the call will be dropped shortly after. Beyond frustrated with this issue. I've read about the LTE and spark issues on sprint w this phone. Best Buy and sprint keep saying this isn't a known issue. Switching to CDMA worked great for 1 whole day. My 14 day return policy is up at Best Buy so I'm stuck with this phone....What do i do now?

Are you able to make or receive calls at Best Buy? If not, they kinda have to deal with the problem, on the spot. If it works, then is it a network issue at home? Does WIFI calling work? Also check for updates. There was one today and that may clear up any software issue, not that I really think that is the issue. I also doubt it's a hardware issue, since this is your second phone. These are really solid phones and although there are some defects from time to time as any other phones have. Go to Best Buy and or Sprint...

[elshagon]

These are the instructions I used when I had similar issues a couple times. It fixed the problem for me and is worth a try for you:
Go into the phone app, dial ##72786#, open the top right menu, and select "reset". it'll look like it's resetting the phone back to factory, but it just ends up rebooting.

As near as i can figure, it resets the communications drivers on the phone

[Issey Miyake]

I would say it works about 10% of the time, but calls will drop after 10-60 seconds. So it sounds as ifs its a network issue. Was at Best Buy for 3+ hours they tried to swap the phone again and it did the same thing with the brand new out of the box phone. We were gonna get the Samsung S5 and be done with it, but they said its past the 14 day return policy. Not sure about the wifi calling I'll check for updates. Went to Sprint and the Tech guy was just leaving on a 50 min lunch break :/ Sat there with someone else and we tried switching the network to CDMA and that fixed it, everything worked just fine. 1 day later I'm back with the same issues on CDMA. Going to try elshagon's instructions and check back.

[mfreeland]

It really does sound like a network problem. Still think I'd be making calls at Best Buy (to the tech guy) so that they can see the problem. They have to fix it.......

[dlocks]

If you are going to try elshagon's suggestion make sure wifi is turned off

[mfreeland]

If you are going to try elshagon's suggestion make sure wifi is turned off

Where did he say to make sure WIFI is off?

[johnmcc0710]

Who is your carrier? I am with Verizon and unless mine is on Global otherwise I have problems with calls.

[dmoss7]

Could it be your SIM card? If it's carrying over from phone to phone, the two least common denominators would be the network or the SIM card (with the assumption that the same one is being used in both phones)

[dlocks]

Where did he say to make sure WIFI is off?

He did not say, from my understanding wifi does not have to be off, but you cannot be connected to a wifi network.

[Issey Miyake]

Carrier is Sprint. It seems to work on CDMA outside of my city, but once i get back into town I get the same issues. Tried that reset and still nothing. Guy at Sprint said no other HTC One M8's were coming in with this problem. Wtf. Not sure if Best Buy swaped the SIM cards or not. Will try that next.

[ollieg]

and you tried updating the proifile and PRL
as well as the 3G-only mode?