Sound won't work but only on Apps

[mynameispercy]

Hi there, i wonder if anyone can help me?

I bought the new i phone 3Gs yesterday, all seems very well, enjoying the features etc, works fine.

However i have downloaded a few apps, some of which i have paid for, and the sound doesn't work on any of them. Downloaded celebrity soundboards for a bit of a lark and it doesn't work and the sounds on the games doesn't work either. The sound works perfectly on stuff like youtube and music,it is just the apps!

The only time i can get the sound on the apps to work is if the headphones are in, which isn't ideal.

I'd be grateful for any advice.

Thanks

 

[Gav2k]

Turn your phone off of silent and volume up before you launch the app.

 

[mynameispercy]

ok this may sound totally retarded but how do i know if it's on silent. In my settings i am going to sound and vibrate and ring are set to on but the phone doesnt ring when someone calls only vibrates.