I had a play with it, and have determined:

- The volume level at shutdown time doesn't seem to affect the pop. I can crank it down to zero, remove and reinsert the player, and the same pop happens during the boot.

- It isn't related to whether there was a track playing at shutdown time. I got the same pop even at "end of playlist".

Something occurred to me:

What if this isn't even something Voladj is doing actively? Perhaps it's more like this:

Somewhere in the player startup routines, it resets the DSP, which causes a pop. Or something like that. Now, normally, the player's got its outputs muted when it does that. But something about your altered kernel causes the volume to be turned up at that time instead of muted. You didn't make the pop, you just allowed me to hear it.

The only reason I hear it when I select the ioctl with voladj is because that's instantaneous, and the player startup routines come right after that.

What do you think of that theory? Hare-brained?

Wait... no, that can't quite be it. Because I've got that "getkey" thing running as the very next item in my init script. It waits a few seconds on a blank screen before launching the player. The pop happens after I invoke ioctl and before that getkey thing runs. There's something happening at that moment which I'm not understanding. Hmmm....

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Tony Fabris