Hikvision 7716 Recording Problem

I had a 7716 for about 2 months with all HiKvision cameras. Installed (4) 4TB hard drives and 11 cameras set for continuous record. All was good.

Two weeks ago I installed a 12th camera and set up exactly the same as others. I keep getting a recording exception for CH12 and obviously that channel does not record. I swapped the cameras bewteen CH11 and CH12. Recording problem did not follow camera (stayed on CH12)

Four days ago, I noticed CH2 still had the record symbol, but NVR said there no record files when I tried playback. I was only trying to playback that one channel.

I lowered resolution on all the cameras just to check to see if it was bandwith issue, it wasn't. The NVR can handle 100Mbps and I am using less than 70Mbps.

The NVR and cameras are not Chinese.

NVR firmware was upgraded to latest 3.4.4 -- Hikvision's only recommendation.

Anyone have any ideas?

Thanks

Update -- Hikvision tech called and rerquested NVR configuration file. He discovered under the HDD settings that CH12 was not set to record. Stupid me did not realize this was evern an option that I had obviously discovered earlier in setup. Anyway, kudos to Hikvision for their support.

As far as CH2 not recording at times. This also started to hasppen on CH5 and CH9. To fix I went in and deleted all recording options and saved. The went in and setup the recordjing options and changed. It has bee almost two weeks now and everyhting is working fine.

I am impressed with the 7716 NVR, the cameras, and their support.

Waiting on devlivery of an outdoor Hikvision 4220 PTZ and the Huisun mini 10X PTZ.

My setup --

DS-7716NI-SP/16 NVR with (4) 4TB WD purple HDDs

(7) DS-2CD2332-I5

(4) DS-2CD2132F-I2

(1) DS-2CD2332-I2 I use as a LP reader on my driveway