It already does say locked. The issue is that you shouldn't be able to select a locked item from a quick-access pop-up. That's a big hit to usability and style points. If you want to see the volume level you can still access it through the main player menu.

When I lock the volume it's because I want it fixed at that level. I dont want to see it again. I use my head unit for volume, the empeg is just a source device.

I'll likely use Hijack to completely remove the push-button items for something more useful in the end if all these items become redundant.

Bruno