For the first issue, have you ever been able to get sound when receiving a text message? If not, you have to set up the profile to enable sounds, which we can help you with if you have not done so yet.
I would suggest both of you do a battery pull while the phone is on, sometimes there is a hang up with picture messages I have noticed, and this generally helps me with my issues.
I was having the problem with hearing the sounds with mms recently. I noticed on the "slide" at the top left was the word "mute". While in the mms, I hit the volume up key and I am now able to hear my mms.
Hope this helps.
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