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MKV audio delay with Roku Media Player (works with MP4)
Roku Media Player introduced an audio lag (audio lags behind video, variably from 200-600ms) ever since the 9.4 Roku OS update.
I have a TCL 55R615 Roku TV (Roku model 7120X) running the 9.4.0 Roku OS (build 4190-30).
I store all my video files on a WD-EasyStore hard drive, connected to a USB port on the TV (using a USB 2.0 bridge, because a TCL TV won't recognize a USB 3.0 device).
Ever since the 9.4 OS upgrade, all my files played on the Roku Media Player have an audio lag of variable length.
All my files are wrapped in a MKV file container using MKVToolNix. They've all worked fine for months, until this last patch.
I've done all the basic troubleshooting steps for audio and video lag mentioned in these forums and others across the internet.
My video codecs are either h.264 (AVC) or h.265 (HEVC).
My audio codecs are usually AAC 2 channel at 196k.
Since the lagging started, I started using different codecs hoping to fix the problem. I've tried Dolby Digital (AC3) and Dolby Digital Plus (E-AC3) [2 and 6 channels, and different bit samples], even tried PCM.
I tried different USB drives, and nothing worked. The lag was there.
Streaming Netflix has no audio problems, it seems to be solely Roku Media Player.
I decided to wrap some of my movies and shows in a MP4 container using FFMPEG, and play them on the Roku Media Player. They had no issues. All I did was demux the MKV files into their respective audio and video tracks (with FFMPEG), and re-wrap them in an MP4 container (with FFMPEG).
So, I know there is not an issue with the Roku Media Player "reading" or "interpreting" the audio codec, because the codec (audio tracks) are the exact same from my MKV to MP4 files.
I don't want to reconvert all my MKV files to MP4 to get them to work with Roku Media Player. They all worked fine prior to the 9.4 Roku OS upgrade.
Re: MKV audio delay with Roku Media Player (works with MP4)
That's interesting. Does the Play USB channel/app use the old style UI? It's pretty much impossible for a channel/app to have a bug when it comes to playback since all it does is tell the firmware what to play. I'm wondering if the bug is in the new video player component vs. the old.