Occasional problem with phonecalls

[Otumelty]

Hi all,
I have a 16gb 4s, and my problem is every so often (maybe once in every 10 calls made) the call doesnt go through to ringing the person I have tried to call, but the phone itself doesn't cut the call off giving the "call failed" it just says on the call, and when I press "end call" it just says "call ending" and it doesn't end the call, i've left it for upto 5 minutes sometimes waiting to see if the call will cancel, and it doesn't and I'm forced to turn the phone off just to get the call to end.
Any ideas?
Thanks

 

[Shadowbech]

Have you tried restoring your phone? It may be a corrupt data within the iOS. So re-install the iOS firmware by putting your phone into DFU mode. If you don't know how to put your phone in DFU mode, Google it.

Try restore from back up, and if it still does it, then restore as a new phone and see if this helps. Your last resort is to take it to the apple store and have the genius take a look at it.

 

[Otumelty]

Thanks, I'll try that now, and let you know how it goes in a few days, it sort of comes and goes