[Linux-based NVRs] Why I can't hear any audio from a 3GP recording file when using Windows Media Player?

Question

Why I can't hear any audio from a 3GP recording file when using Windows Media Player?

Answer

3gp is the main video format used to store videos in Linux-based NVRs (as well as VAST2) because its compression reduce the size of the file allowing to store more data in your drives. Even though, most player nowadays support this format, you might need to download specific codecs to be able to visualize the whole data. This is the case for the Windows Media Player, you will require a specific codec to play audio from 3GP files in Windows Media Player. If you don't have the necessary codec installed, you won't be able to hear audio. You can try installing the K-Lite Codec Pack, which includes many common codecs.

You can also try a different media player such as VLC or KM player which come with built-in codecs and may be able to play the audio without any additional installation:

• VLC Player webpage: https://www.videolan.org/vlc/ 
• KM Player webpage: https://www.kmplayer.com/home 

If none of the above solutions work, you can try converting the 3GP file to a different format using a video converter tool to a more common codec such as MP4.