If you’re like me you use the text to speech feature of IOS quite often to read you articles, emails, and other things. One thing I noticed quickly after updating to IOS 7 this morning was that, at least when it comes to text to speech, Siri’s voice was muffled, somewhat unclear.
It turns out Apple is not shipping the entire voice library necessary to have the clearer sound we’re used to. To fix this go to Settings-general-accessibility-speak selection-voices-English and turn on the enhanced quality option. This will download an update that will make everything sound much clearer and as you’re used to.
Living Critic 
Thank you for that! Yes my Siri is sounding muffled (very robotic, more like a Cylon from ’70’s Battlestar Galactica) since the iOS 7 update. I was worried I was the only one having problems! I’m sure there are more important things in life to worry about…still, you’ve solved my problem!
I’m not sure your trick is working…on my ipad it´s not.
Oops it´s actually working 😉
The download for me just says ‘preparing to download…’ But nothing actualy gets downloaded!?
Having the same problem, Lee S. Voice is terribly robotic and was not updated to the natural sounding voice. But when I go to download the enhanced quality voice, it just says, “preparing to download…” the entire time and nothing else happens. So frustrating.
I use I-call’s free version, and it hardly ever works. Most of the calls that I make are not understood by the person that I’m calling, and I run 20 m Click https://zhoutest.wordpress.com/