connecting to beep device driver

Hi!

I’ve made a small kernal device driver and would now like to make a beep
from the speaker. I’ve tried to connect to the running beep.sys with
ZwCreateFile and ZwDeviceIoControlFile commands. I get no errors with this
but there will not come any sound out of the speaker. Until now I’ve
bypassed it by using HalMakeBeep(freq.) and a connected timer. I would
rather use the beep driver to take care of the beep. Anybody that got the
knowledge how to make it work?