My IPC cams were changing their time and time zones no matter how many times I reset them. Plus the playback video was out of sync was usable with glitches in playback. If you have the same problem I found the solution online.
You default the time screen, turn off DST, turn off NTP, don't worry what time zone it is anymore. Set the time on your NVR. Then do the same to each camera. Once you stop the IPC cameras from seeking time changes, the IPC has to get the time from your NVR.
Come Nov and March change the NVR time by one hour and the cameras will change automatically.
After you have IPCs synced with NVR time your vidoe playback will by in sync and smooth like it should be.
Hope this helps someone. I was perplexed for days and now my NVR is running smooth.
If anyone has a better "fix" let me know.
NVR is a 8 ch Pentabrid HDOC brand new last week. It does IPcams, HD-CVI, but I only have IP cams on it.