While setting up a stereo in another room I decided to use VBAN with an older cellphone to send the audio from my PC in the bedroom as the audio from the wireless HDMI extender I used isn't all that great.
Using a signal generator app on my PC I discovered the output at 20kHz causes the input level in VBAN receptor to drop by 1 bar on both channels.
That cellphone has a 44.1kHz sampling rate according to VBAN Receptor.
I tried my new cellphone which has a 48kHz sampling rate according to VBAN Receptor and same issue.
I can connect an oscilloscope to a quality bluetooth receiver that I verified is flat to 20kHz using an audio generator on my phone and can see the drop in output.
I even tried a nearly 2 year old Windows 11 PC and have the same issue.
The sampling rate from VBAN is 24 bit 96kHz. The main stream sampling rate is 24 bit 192kHz.
I verified that it wasn't the app by connecting the scope to a quality sound card and no drop in audio at 20kHz.
To verify it isn't VBAN Receptor I sent audio to another PC using VBAN and same problem.
Upgrading to the latest Voicemeeter Banana version didn't fix it.
Any reason why VBAN would be causing this issue?