What would be the benefit of using this instead of the Fiio app?

Huh, yeah. Now that you point it out, I was experiencing the same thing and didn’t really notice it. I just kind of poked around until I got what i wanted.

Great, thanks! Something to put on my wish list then.

Sorry, I mean what's the sound quality benefit? How would the AK PA10 improve the sound over the Q15's built-in amp?

Because I don't understand all this to that extent (yet), what exactly is the benefit of spending another $600 on the PA10 combined with the Q15?

When I first tried this, I had the source connected via USB-C (either an iPhone 15 Pro Max or an iPad Pro 11 M2). Turning MQA off with the source connected messed up the USB-C configuration in the source somehow and volume was as you're experiencing -- drastically lower to the point where it was...

Sure, that makes sense. But then, it would appear that PEQ is indeed working with the latest firmware.

Except correct me if I'm wrong, but the Q15 no longer has issues with PEQ or major issues with the firmware. Yes, you have to turn MQA off to enable PEQ, but I'm not sure if that's actually an "issue."

The PEQ does work in USB mode, but you have to switch MQA off to enable it and, in my experience, you can't be connected to your source when you do. When mine was connected to my iPhone and I made the switch, it confused the iPhone and I had to remove and then connect it again. When I unplugged...

The latest firmware update fixes a host of issues. I've found the Q15 to be pretty close to perfect once I installed it. I do have an issue where I need to unplug the source before switching into/out of MQA mode to enable/disable PEQ. Keeping it plugged in causes general wonkiness. And, I'm not...

Yep, the download works for me.

I think that screenshot is for a different device. The Q15 only shows LO and PO in the 3.5 (SE) output selection. Same with the 4.4 (Bal) output selection. And the Coax on the Q15 is input only, I'm pretty certain.

Doh! "PO" = "power outlet." I should have been able to figure that out myself. I blame too much going on.

Okay, thanks, I was wondering about that setting. So LO = line out, I'm assuming. What does PO stand for?

Okay, thanks, that's what I thought but my iPad in particular seems to burn a lot of battery when I'm playing with both switches on. I'll have to pay more attention and see what's happening.