Enable sb and drvctrl in the kernel. the `opl` error is harmless.
sb0 at isa0 port 0x220-0x22f irq 7 drq 1: dsp v2.01 audio0 at sb0: playback, capture, half duplex audio0: slinear_le:16 -> ulinear_le:8 1ch 12500Hz, blk 124 bytes (9.9ms) for playback audio0: slinear_le:16 <- ulinear_le:8 1ch 12500Hz, blk 124 bytes (9.9ms) for recording opl at sb0 not configured
Our early FreeBSD attempts to enable sound support under 4.x were with the following kernel options:
device pcm device sbc0 at isa? port 0x220 irq 7 drq 1 flags 0x15
... followed by the standard MAKEDEV:
# cd /dev # sh MAKEDEV snd0
This results in the following dmesg output:
sbc0: <SoundBlaster 2.0> at port 0x220-0x22f irq 7 drq 1 flags 0x15 on isa0 pcm0: <SB DSP 2.01> on sbc0
Unfortunately, attempts to use mpg123 and waveplay only chewed up a bunch of CPU time, didn't produce any output, and didn't terminate without user intervention.
The following deprecated (snd) VOXWARE driver settings actually work:
device snd0 device sb0 at isa? port 0x220 irq 7 drq 1 device sbxvi0 at isa? drq 7 device sbmidi0 at isa? port 0x330
... giving the following dmesg output:
sb0 at port 0x220 irq 7 drq 1 on isa0 snd0: <SoundBlaster 2.1> sb0: driver is using old-style compatability shims
... but you have to pass mpg123 a "-2" flag to step it down because it can't play 44100 for some reason (it may require more CPU power than the machine has?)
No one has successfully gotten sound to work under FreeBSD 5.x yet that we're aware of.
For reference: the sound section of the FreeBSD Handbook.