ATT Samsung GALAXY S3 and pro hd slingbox

[fjmckey]

my galaxy 3 jellybean,,, limit to 632 kbps when streaming with slingbox in the att red,i check all the settings in phone and in slingbox applicattion and not found the reason for this limit ,when i using the slingbox via wifi in the galaxy s3 streaming at 4118 kbps obvious the phone didnt has this limit of 632 kbps ,the slingbox didnt has a setting to limit the streaming .
if any one knows something about this ,thanks in advance for any comment..