Have you set custom ringtones for certain contacts in your address book? If you have you have to set a message alert for them as well, otherwise it will just play a default sound.
If that is not what you have done, try setting up a custom Sound Profile. Some users reported similar issues, and setting up a custom profile solved it for them.
I have this same issue and I don't have custom profiles or rings for anyone. It only started doing this after I upgraded the OS that was recently available for the torch. Any ideas?
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