Voiceover crashing and exiting a program in BBC Iplayer

Hi, I've just had Voiceover crash whilst using the BBC Iplayer app and I've had to use Itunes to get it to speak again. Does anyone know how to exit a program once you've listened to it on Iplayer? VO won't let me navigate around the screen. Anyway, I exited voiceover with the triple click of the home key but I was unable to restart voiceover again by tripple pressing the home key again. I tried restarting my phone a few times but in the end I had to use Itunes to activate it again and normally the speech rate is set to 100% but it was set to 30%. Has anyone else come across this behaviour? Voiceover also seems to crash quite a bit whilst I'm navigating search results in apps or browsing through my text messages. It stops speaking but I still hear the click sounds to say the cursor has moved to the next item. I have to restart my phone usually to get VO to talk again.