cant be sure but i would say it is a problem with dfs's tool.i dont say that to be bias,here is what i base my opinion on. when we moved to the 6x platform we also encountered a "sms bug" it also affected mms a little.we found that bug before release of the support for 6x was put out and corrected it.so it may be that same or similar bug they have in there tool.why dont hit there support up on skype to get help? if i am correct there is no help you can get from any forum for that problem it needs to be corrected in the software and your phone reflashed.so unless you have been fooling with nv items or your account with your carrier has feature code issues that is where problem most likely is