Sheppy, While I think that they were changes in the latest software to the way on-demand is handled. I think the actual cause of your problem is elsewhere - network or hard disk.
It may well be network related and I would be interested to know if you have any problems with access to recordings with booting with the network cable disconnected.
Hopefully the hard disk format will have restored buffer functions for you. If not there have been several users who have recently reported hard disk problems but these have been more the disk not being detected at all. I presume when you have your problems the system - storage settings seem OK?