I've got an ASUS motherboard with a built in ESS Solo-1 sound chip.
It appears to probe happily:

    eso0 at pci0 dev 6 function 0: ESS Solo-1 PCI AudioDrive ES1946
    eso0: interrupting at irq 5
    audio0 at eso0: full duplex, mmap, independent
    opl0 at eso0: model OPL3
    midi0 at opl0: ESO Yamaha OPL3
    mpu0 at eso0
    midi1 at mpu0: ESO MPU-401 MIDI UART

and programs play to it, but it doesn't work; I just get a some
low-level, long steady tones from the left speaker when I try to
play anything. It also makes some noise when nothing's playing to
it, in particular, a chattering noise when the hard drive is being
accessed.

It works ok under Windows.

Any thoughts on what might be going wrong here?

I'm running a quite recent kernel:
NetBSD agnostic.cynic.net 1.4P NetBSD 1.4P (GENERIC) #0: Wed Jan  5 13:18:11 EST 2000

cjs
-- 
Curt Sampson  <cjs@cynic.net>   917 532 4208   De gustibus, aut bene aut nihil.
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