[linux-audio-user] rec creates empty files, play plays nothing

[ed orphan]

The Creative SBLive - Emu10K1 mixer
has 3 little boxes under most of the slots. For example,
under  IGain are the boxes  Lock  Mute  Rec.
Lock is "checked" for all of the slots on the mixer.
What do these boxes do? I can't find anything about them
on the mixer. Maybe they have something to do with
rec creating empty files?  I don't know. I'm just guessing.