Solved Video corrupting on rendering VMS 15

I have been trying to edit 4K footage in VMS 15. The original footage looks fine but once imported into VMS the footage seems to corrupt. There are visible horizontal tears or horizontal lines of pixelation across the footage when rendered. If I delete and re-import the footage the problem may go away but reappear elsewhere. It's hard to see whether the problem is visible in the trimmer but is very obvious when rendered.
I have tried rendering using GPU acceleration and without. Using Magix AVC/AAC MP4 format.
I have tried 'Reduce Interlace Flicker'.
None of these seem to work. Any ideas as to how I could solve this?
VMS v15 (build 116)
Windows 7
Nvidia GTX 1050 Ti
Camera - Panasonic GH4 - MOV files

It is rare to see those types of artefacts, in a video rendered with Vegas.
This type of problem is normally caused by Graphics Card Driver issues and/or Video Codec issues.
It may be difficult to work out what is the actual problem, so you will have to be patient and do lots of testing.

It could be a problem caused by the new Magix AVC/AAC encoder/decoder engine in Vegas Movie Studio 15 Platinum.
I have seen other GH4 owners complain of some problems.

You can temporarily disable the Magix AVC/AAC decoder and use the older Mainconcept decoder/encoder.
Hold the SHIFT key down and go to Options/Preferences/Internal
Internal is a hidden options menu.
Type "avc" in the search box.
Set Enable So4 Compound Reader for AVC/M2TS = FALSE
Set Enable Mainconcept AVC/AAC Render plugin = TRUE
Click Apply and OK and the re-boot Vegas.



When you import 4K video into Vegas, Proxy Video versions should automatically be created.
They may also have been corrupted, so before you test these new settings, go to the folder your 4K videos are living in and delete all the video proxies. They will look like sheets of paper and end with .sfvp0

Now re-open Vegas and import the same 4K video that was showing coloured pixelation.
Set the Preview Window = Best/Full
Does the video now look OK ?
The older Mainconcept AVC/AAC decoder is now decoding the video.

Now you also said the rendered videos had tearing in them.
You need to do a second test and render using the older Mainconcept AVC/AAC encoder.
It will no be showing as an option in the Render As window.

Graphics Card Drivers
Nvidia releases a large number of different Drivers each year.
Every now and then, they may release a new driver that screws up processing in video editing programs.
I have seen weird shit happen myself, when I installed particular Nvidia Drivers.
I would recommend you install a older version of your Nvidia Driver and see if that fixes the problem, if you still experience problems using the older Mainconcept AVC/AAC decoder/encoder.

Hi
Thank you very much for taking the time to reply.
I've tried most of the above and the problem seems to be less evident but not sorted altogether.
I haven't tried doing anything with the graphics card yet but that'll be my next job!
Thanks again. Much appreciated.
Cheers
Steve

After a few weeks of trying to sort out the above problem I decided to check on the RAM installed. The test threw up over 15000 errors so I swapped the RAM and this totally solved the issue.

Very interesting - thanks for reporting back :idea:
I will have to remember this one in the future.

Now that I think about it, I wish I had thought of something else initially.
About 12 months ago, all my video started getting coloured pixels and tears appearing in the Vegas Preview window.
The problem ended up being my Graphics Card was dying.