How to pipe both an audio file and my voice through a voice communication app?

I have a very long audiobook that my friend and I would like to listen to at the same time, so that we can both react to events and pause to discuss, etc.

Since we talk on Discord, I thought it might be possible to figure out a way to pipe both the audiobook audio and my regular microphone audio through the same virtual cable, such that they can hear my voice and my audio playback (from VLC) at the same time. Then I could pause and resume at will and we would never get out of sync.

I attempted this by downloading VB Cable and Audio Repeater

I opened up two instances of the audio repeater application and piped their respective audios like so:

Audio Repeater #1: Stereo Mix -> Virtual Cable
Audio Repeater #2: Microphone -> Virtual Cable

I then set my Discord input device to be the Virtual Cable, and voila, when I hit play in VLC, they could hear both the audiobook and my voice.

Unfortunately, they could also hear themselves, as their voice was coming through my Stereo Mix. In addition, the audiobook volume levels were too low for them, and too high for me.

Is there a better way of doing this? Ideally there would be some simple way that they could hear both me and my VLC at the same time, and I could adjust the volume levels of the audio for them and me separately, all while I can still hear the audio and they cannot hear themselves and I cannot hear myself. Is this do-able? Thanks for reading.

Voicemeeter Banana Explained Simply

You'll also need a program called Audio Router or if you are running Windows 10, audio router.

Banana has 5 Audio Inputs and 5 Audio Outputs.

On the output side, through Control Panel Sound, you will connect VoiceMeter Output as the default device under Recording Tab. I have played video sound over Teams with this setup.

Under Banana. You'll connect your microphone as Hardware Input 1.

In Audio Router, you will use drop down menu to connect your audio software to a virtual cable. Cable-A Input or HiFi Cable Input. I used Opera. You will need your software to be running.

Be aware that Windows can become confused, when Banana or Audio Router is not running and you try to run linked software (no audio out). You have to link software to default device with Audio Router (or do it when you finish with sharing).

Or in Windows 10: Sound Settings -> Advanced sound options -> App volume and device preferences. Connect your audio software to a virtual cable.

Under Banana, you will link Hardware Input 2 to your virtual cable.

Now by hitting B1 on both inputs, you should be able to connect both inputs to default output B1. A1 allows you to hear Audio. A1 must be connected to your earphones.

With the video and this you should be able to work it out. Use Control Panel Sound to verify input and output activity.

And setting up the software (Audio Router and Banana), Banana can become confused. Restart Banana.

I use Banana and Audio Router as required, but I unlink software and make sure default devices are set to default under Control Panel Sound when finished.

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