Ivr not answering incoming calls

I have a google voice number set as an inbound route that is linked to an ivr the problem is that it will work right for about 6 hours but then the ivr will not answer and the number will ring about 5 times and will answer with dead air. I can go in free pbx and re apply the ivr to the inbound route and it will work again. All other inbound DIDs link to an extension and never have any problems.

Thanks for your help

a log of a failed call maybe?

How would I get the log?