Many users face a common problem while playing .mkv or other video files on their smart TV, the video plays but there is no sound. Interestingly, the same file works perfectly on a laptop or smartphone. This usually points to an unsupported audio codec on the smart TV.

Understanding the Problem

Smart TVs, especially budget models, support a limited range of audio and video codecs. While formats like .mkv and .mp4 are widely supported, the underlying audio codec (e.g., AC3, DTS) may not be. Most Android TVs support AAC and MP3 audio codecs natively, but not AC3/DTS unless licensed.

Convert the Audio Codec

Instead of converting the entire video (which is time-consuming), you can simply re-encode the audio stream using a tool like FFmpeg, leaving the video stream untouched.

Installing FFmpeg

  • You will install FFmpeg according to your system. I use Arch Linux. If you are also using Arch Linux like me, then use the following command to install FFmpeg on your system:
    •  sudo pacman -S ffmpeg

Solution

  • If you’re on Linux (or any system with FFmpeg installed), run:
    •  ffmpeg -i input.mkv -c:v copy -c:a aac output.mkv

-c:v copy: keeps the original video stream untouched.

-c:a aac: converts the audio stream to AAC, which is widely supported by smart TVs.

This process is fast because only the audio is being re-encoded, and the video is copied directly.

Check Your Files Codecs

  • To inspect the original file and confirm the audio codec:
    •  ffprobe input.mkv
  • Look for lines like:
    • Stream #0:1: Audio: ac3 (AC-3)

If you see AC3 or DTS, converting to AAC is a smart move.

Final Thoughts

If your smart TV doesn’t play the audio in a video file, don’t assume the file is corrupted. A quick codec conversion using FFmpeg can save hours of frustration. It’s a simple fix that works reliably especially for budget Android TVs that don’t license premium codecs by default.