MPC-HC (64bit) suddenly stopped playing audio from video files.

I can play the files on other software and can hear the sound.
I can confirm that there's an audio track of: Audio: AAC 44100Hz stereo 128kbps [A: SoundHandler (aac lc, 44100 Hz, stereo, 128 kb/s)] inside of MPC-HC

It can play files recorded from an hour ago, with the same settings, same format etc.
I haven't touched any setting, both for recording and for the player but the player suddenly stopped playing the audio tracks.

All I can think of is I might have mistakenly used a hot key for a settings or something. But then why would it play the some of the files and some not.
I also triple checked every setting related to audio, both from player, device settings, mixer settings, filter settings, decoder settings you name it...

I just can't figure out what happened and how to fix it. Would really appreciate some help. Thanks in advance.

Right-click on the volume icon in the Windows system tray. Click on open Mixer. There you can see volume for each individual active application. Maybe player volume is set low there.

Hello thank you for the reply.

The problem turned out to be about the internal audio switcher. I can hear the audio again after disabling it.

I always used to have it enabled with +600 volume gain. I suspect that some of the recordings having too loud audio, with this amount of gain, ended up with no sound.

A +600 volume gain is massive. That can result in overflow (> 100%), which can hurt audio quality. This is the first time I hear that it silences the sound. But maybe there is some kind of overflow protection in your sound driver or speakers.

Better is to use the Normalize option. That will boost the volume only when the volume is low.

Also check your Windows sound settings. If you have stereo speakers or headphones, make sure that you haven't accidentally set 5.1 speakers in Windows.