Is ESS Maestro 3 sound card supported?

I recently got an old laptop, HP Omnibook 6100 with Pentium III 1GHz and 384MB of RAM. I installed Haiku Alpha 3 - it detected network card properly, successfully used non-standard resolution, but I can’t make it see sound card.
The laptop seems to have ESS Maestro 3 sound device, which “should be working” (according to the last message in https://www.haiku-os.org/community/forum/maestro_3_driver ), but when I click on the speaker icon, I’m always getting “Could not find the mixer”.
After installing optional package Opensound and rebooting - no difference. Osstest displays that there are no OSS devices.
Any chance of getting sound from this machine?

Listdev outputs the following info about sound card:

~> listdev

device Multimedia controller (Multimedia audio controller) [4|1|0]
  vendor 125d: ESS Technology
  device 1998: ES1983S Maestro-3i PCI Audio Accelerator

P.S. Sorry for my English