Here's an interesting problem on a brand new HDR-1100S. After using the STB for a couple of days it has decided to not let me record the channel that is being watched live! This happens when using the record button on the remote from the EPG, Now and Next banner or just the 'plain screen". It will also not record any other channels from the EPG that are 'on now'. All future programmes can be set to record.
I've solved the problem by power cycling the unit, but it's an interesting issue nonetheless.