He got a new sim and he had the same problems. He took the phone to the Samsung repair center here and they said the phone was not under warranty anymore as he had the glass replaced when it cracked (2 weeks after he got the phone).
I took the phone from him to see if I could figure it out and as soon as I booted it up, it started to update to 4.4.2. When it finished, the phone was barely useable, lagging so bad the phone would not respond for 5 to 10 seconds and the screen would jitter up and down. I reset the phone twice and though it is better, the phone is still laggy (not as bad) and when I try to make a call, the call goes through, but I hear nothing.
I want to downgrade to 4.3 and hope the phone is better as I have read a lot of people are having trouble on 4.4.2, but with the new 4.4.2 bootloader, I can't downgrade. Is there a way to downgrade that will not trip the Knox counter? Also, has anyone ever heard of people receiving a call getting a loud sound on their end with the S4?