Heya @Asterix201252 , thanks for coming back to us about this! I understand the troubleshooting we've recommended doesn't help, and you still hear this unusual knocking noise.
To try to narrow this down though, so that we can more easily reproduce the issue on our end, can you perform one further troubleshooting step for me?
Please try playing the game with another audio output. The easiest way to do this is to use a USB or bluetooth headset or headphones (as opposed to a 3.5mm headset or headphones that goes through your existing sound output). Don't worry if this isn't something you are able to test - I know it is dependant on having access to another audio output.
Either way, can you also tell me what sound drivers you are on? The easiest way to check this is to right-click your volume icon in the system tray where the clock is, choose 'sounds,' then right-click your sound output and choose 'properties,' then 'properties' next to the controller information, then the 'driver' tab. What manufacturer and driver version number is listed there?
Please let me know if I can clarify these steps further, and thanks again for your report of this issue - I really appreciate it!