When I use the headphone out on my Mac Mini to my Apollo 8p channel 1 via a 1/4", it sounds horrible. Not sure why the quality is so bad and wondering what basic thing I’m doing wrong, late at night.
the most common problem when using a powered output (like a headphone output) is having it too loud, so it overdrives (sounds like distortion) the input of the device that expects the input to be at line level (i.e. a lot lower).
So the first thing I’d try is to turn the volume for the headphone output really low and turn up the input volume on the Apollo accordingly.
In addition: It sounds like you’re connecting a stereo output to a mono input. – So you may end up with just the left or right channel, rather than both. Or a bad mono mix ( depending on what kind of cable you’re using to connect the two devices).
Does the Apollo 8p have Loopback?
This is a feature available on some interfaces which routes system audio back through the interface - thus recording all digital all the way. It is possibly some on the apollos after a quick google search but I didn’t find an “8p”.