I ordered the 920 (and I was very close to getting the 8X...). The 920 does have an audio equalizer (something WP7 devices didn't have..., but I hear you about Beats Audio. I listen to music much more than I take pictures. I hope I made the right decision... Can somebody with a 920 let me know how the audio fares???) C PS: I ordered the Yellow 920.
The audio on the Lumia 920 is pretty good. However there are some minor issues with it. Here are some points:
Sound is very clear, better than Lumia 900.
Equalizer sounds fine. However it is a bit fiddly to adjust the levels of each band. As soon as you lift your finger, they seem to jump a little bit up/down from where you want them. I did turn off the sensitive screen but it didn't help. It's not a big issue but a little annoying.
There seems to be some sort of "widening" done on the audio, which is a bit excessive in my book. This is a very common technique to expand the stereo image (in fact many years ago I wrote an audio plugin for SAWStudio that did just that, it's a simple math formula to expand the audio image). I wish there was a way to turn it off.
Not loud enough, but most phones seem to suffer from this. Different headphones could help here, especially if they are wireless where they have their own amplifier. Also, the trick where you increase the level of all bands in the equalizer to increase overall level doesn't work here because the overall level is reduced as you increase band levels, effectively having no effect on the final output level.
Don't get me wrong, it sounds great and I don't think you will be disappointed. Those are all minor issues really. Most people would be more than fine with the sound.