The one you mention seems to lack a mic. I used one of the Hikvision cube range, like this Hikvision DS-2CD2442FWD-IW | 4MP Wireless WDR Cube Network Camera
Most of the range that support sound actually need a microphone attached. It’s a shame really. Built in mic is so much easier.
The NVR defaults to continuous recording, so mine 'just worked'. Can you try switching the network cable to another of your NVR ports. If it's been left alone, it should just record 24/7.
It all looks like my working system. Might be worth a check in the advanced settings of the schedule, but can't imagine what might be wrong there.
Standard advice would be to turn it off then on again! Check the NVR firmware is current in case of a bug.
Are the recorded files times of motion...
I think the delay starting the stream could be the player waiting for a genuine I frame before commencing play. In H.264+ they suggest 8-12 seconds between I frames.