Hey there tommyrxe and thanks for the question.
When you're trying to send an MMS or audio file, were you using the DIGITS app or going to the web interface through browser? I'd also like to know if you've only used the tablet device and noticed this.
It's not really an issue per se as it is a suggestion for improvement. Would like to be able to send a voice message from within the DIGITS app seamlessly like one does with their phone. At present, you have to exit DIGITS, open up a recording app, record your message, save the recording to a file, then go back into DIGITS, and attach that file to the message you wish to send.
I was suggesting a better seamless way where you might just add a mike button in the dialog box, record your message, then another box opens to play the message before sending it Then once satisfied with the message, hit send to send it. Just a possible suggestion for seamlessly sending a voice message from WITHIN DIGITS.
Overall by the way, I'm enjoying the app. I'm hoping to be able to continue to use it past the beta period and am hoping it will be available free at least to us beta testers. But I also feel it could/should be free to all as a valuable perk/extra value added item to entice people over to T-Mobile with this unique to T-Mobile only feature (maybe via a check box from within "My T-mobile" much like the WIFI calling feature?).