GP2013 on SQL2012 Timing Out?

I have a client where people who leave MDGP 2013 untouched for a while receive an error message stating "A remove range operation on table 'syContentPageXMLCache' cannot find the table" when they resume using GP.

The More Info is "[Microsoft][SQL Server Native Client 10.0][SQL Server]Invalid object name '##1675106'".

It looks to me like it might be a timeout but I wondered if anyone could shed more light on the issue? Hopefully including a resolution.

This is Microsoft Dynamics GP 2013 running on SQL Server 2012.

Thanks.

Ian