# Cannot HW Transcode MP4 videos **URL:** \ **Category:** Plex Media Server\ **Tags:** server-windows, android-tv\ **Created:** [March 10, 2021, 2:33am UTC](https://forums.plex.tv/t/cannot-hw-transcode-mp4-videos/698776 "2021-03-10T02:33:46Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![FlaTechNole21](https://avatars.discourse-cdn.com/v4/letter/f/a587f6/32.png) [@FlaTechNole21](https://forums.plex.tv/u/FlaTechNole21)\ **Post date:** [March 10, 2021, 2:33am UTC](https://forums.plex.tv/t/cannot-hw-transcode-mp4-videos/698776/1 "2021-03-10T02:33:46Z")
Server Version#: 1.22.0.4163 Player Version#: Plex for Android 8.13.2 on NVDIA Shield 2019 Pro My PMS attempts HW Decode/Encode per my settings, but fail and resort back to SW transcoding. I have the i5-10210U CPU with Intel UHD Graphics Driver v27.20.100.8681. I access it by RDP, but I do also have it connected to my TV just in case. According to the [PMS logs,](https://support.plex.tv/articles/200250417-plex-media-server-log-files/) h264\_qsv and h264\_mf encoders fail along with the dxva2 decoder. The fail messages are: “[FFMPEG] - Failed to create Direct3D device” and “Codecs: hardware transcoding: opening hw device failed - probably not supported by this system, error: Unknown error occurred” This happens with 8-bit h264 and 10-bit HEVC mp4 sources (both 1080p and 4k). This is not an issue with my mkv files. I tested further by creating mkvs from my test mp4s, and they did HW Transcode. ---
**Author:** ![FlaTechNole21](https://avatars.discourse-cdn.com/v4/letter/f/a587f6/32.png) [@FlaTechNole21](https://forums.plex.tv/u/FlaTechNole21)\ **Post date:** [April 16, 2021, 3:47am UTC](https://forums.plex.tv/t/cannot-hw-transcode-mp4-videos/698776/2 "2021-04-16T03:47:46Z")
So I decided to check if this was an issue on my Windows Plex app and it is not. During a forced transcode, Windows performs a hw transcode and converts aac to opus. My two Android TV devices (Shield/Sony Bravia) and Android phone seem to be the only ones that don’t hw transcode mp4 files. I noticed that Android is also different in that it transcodes aac to aac. I thought transcoding was a server-side task, so I’m confused why the player matters here. ---
**Author:** ![BobSnot](https://avatars.discourse-cdn.com/v4/letter/b/94ad74/32.png) [@BobSnot](https://forums.plex.tv/u/BobSnot)\ **Post date:** [April 16, 2021, 3:52am UTC](https://forums.plex.tv/t/cannot-hw-transcode-mp4-videos/698776/3 "2021-04-16T03:52:44Z")
just for interest, Intel shuts down the decoders/encoders if it does not detect an ACTIVE screen connected. You may find that it works when your TV is on and showing the server display and not at other times. one of these types of devices may help → [https://www.amazon.com/Headless-Display-Emulator-Headless-1920x1080-Generation/dp/B06XT1Z9TF](https://www.amazon.com/Headless-Display-Emulator-Headless-1920x1080-Generation/dp/B06XT1Z9TF) ---
**Author:** ![FlaTechNole21](https://avatars.discourse-cdn.com/v4/letter/f/a587f6/32.png) [@FlaTechNole21](https://forums.plex.tv/u/FlaTechNole21)\ **Post date:** [April 16, 2021, 3:57am UTC](https://forums.plex.tv/t/cannot-hw-transcode-mp4-videos/698776/4 "2021-04-16T03:57:15Z")
It’s connected to my TV for that reason. If that were the case it wouldn’t have properly transcoded on my Windows app (not on the server PC) ---
**Author:** ![BobSnot](https://avatars.discourse-cdn.com/v4/letter/b/94ad74/32.png) [@BobSnot](https://forums.plex.tv/u/BobSnot)\ **Post date:** [April 16, 2021, 4:25am UTC](https://forums.plex.tv/t/cannot-hw-transcode-mp4-videos/698776/5 "2021-04-16T04:25:41Z")
restart the server, watch something that isn’t working for 2 mins, then post server logs > **[Plex Media Server Logs | Plex Support](https://support.plex.tv/articles/200250417-plex-media-server-log-files/)** > > Log files are an important tool that can be used to help investigate problems you may be having. It’s important... ---
**Author:** ![system](https://global.discourse-cdn.com/plex/original/3X/2/a/2acb9765406f63293d357b4ec509ec39aa28f2ad.png) [@system](https://forums.plex.tv/u/system)\ **Post date:** [July 15, 2021, 4:26am UTC](https://forums.plex.tv/t/cannot-hw-transcode-mp4-videos/698776/6 "2021-07-15T04:26:33Z")
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