After a recent update to Windows 10 and AudioBox drivers, I am suddenly only getting mono sound from my headphones attached to my AudioBox USB. This is when I'm not running Studio One. I have input jacks 1 and 2 connected with a stereo input signal which I chained from a second PC. This way I can get audio from a second PC. With the PC that is connected through USB to my AudioBox, I get stereo output from the "Playback" side of the mixer, and nearly 0 output when dialed all the way to "Input".
With my secondary PC output connected to the input jacks 1 & 2, I get mono output from the headhpone jack and external speakers when the mixer is dialed all the way to the "Input" side and nearly 0 output when dialed all the way to "Playback". This is mostly expected, except for the output being in Mono (output from both sides of the headphone speakers, but it's not split stereo. This is verified using a Stereo Test video from YouTube which plays sound on left and right channels independently, but I hear the sound on both sides always.
I can work around this issue when I run Studio One, where I can route the input signals to stereo ouput and turn the mixer dial to the "Playback" side to hear the sound in stereo. However, it's not great that I have to start Studio One each time, and it's obvious after playing a YouTube stereo test that the signals from the PC into the input jacks of the AudioBox are, in fact, split stereo (since the routing from within Studio One works).
So, my question is, how can I get back to hearing stereo directly from the input signal when my mixer dial is dialed all the way over to the "Input" side?
AudioBox firmware v2.70
Universal Control 3.3.0.59348 Win x64 (Built on Jul 3 2020)
Studio One Artist (4.6.2.58729 Built on July 3 2020)