Other Help Topics :: Good book or articles on DSL components?

Hi, newbie here. Does anyone know what that little box in the bottom right corner is for with the dMix, M, floppy, and unmounted buttons?

Try the DSL book

The box has your volume settings (dmix, m(ute)) and a mount tool. Also read the page that opens when you boot DSL..

I read the Help, and there is zero mention of that little box, dMix or mounting.

If you hold your mouse pointer over "floppy" without clicking, a help box will pop-up - the same goes for "unmounted".

original here.