Firmware Upgrade for DS-2CD2742FWD-I + DS-7608NI-E2/8P/A

I was wonder if any one knows the URL for the firmware upgrade for these cameras + NVR DS-2CD2742FWD-I and NVR DS-7608NI-E2/8P/A . For the past few days one of my cameras is being turned off and needs unpluging from the NVR and resetting the NVR before it will restart . I have had this in the past and all was well once the firmware had been updated which was about 1 year ago . If I unplug the internet from the NVR it runs fine but as soon as it been on a few hours the same camera is turned...

Firmware Upgrade for DS-2CD2742FWD-I + DS-7608NI-E2/8P/A