jbrooks0801
Could you do the following and report back:
1 Install MPC-BE
https://www.videohelp.com/software/MPC-BE
2 Install LAV Filters
https://files.1f0.de/lavf/nightly/
3a Go to MPC BE options "Video" and select "Enhanced Video Renderer (Custom Presenter)" from the drop-down list
3b Got to "Audio" tab and select your sound-card
3c Go to "Subtitles" and slect "internal subtitle renderer"
3d Go to "Subtitles\Rendering" and select "Desktop" from the drop-down list
3e Go to "Internal Filters" and disable all filters in the tabs Source Filters, Video Decoders and Audio Filters
3f Go to "External Filters" and "Add filter" select "Lav splitter Source" and then tick "prefer" do this for "Lav Video Decoder" and "Lav Audio Decoder" as well (in that order)
3G Double click "Lav Video Decoder" change "Hardware decoder to use" to DXVA2 Copy-Back, DXVA2 Native or CUVID whichever is able to play your 4K files (Change apply and restart MPC BE each time)