Connection Stuck on "E"

[grainyrice]

Recently, I flashed the CyanogenMod 10 Stable Release on my T-Mobile SGS3.

Ever since that flash, I've been getting "E" or "G" on my data connections intead of the usual 4G/3G.
As a result of this problem, I odin'd back to stock following one of Qbking77's YouTube videos, and it successfully worked.
However, the mobile data problem still remains, does anyone know of any fixes?

Thanks in advance.

 

[ipwn3r456]

I want to ask, what kind of data plan did you get for your SGS3? Unlimited with 2GB high speed data, unlimited with 5GB high speed data, unlimited with 10GB high speed data, or Unlimited Nationwide 4G? If you have one of the first three, after certain amount of "high-speed" data usage (either 2GB, 5GB, or 10GB), then after you will stay with either GPRS or EDGE speeds. That might be the problem.