I already sent bugreports about broken sound after OpenBSD 5.7. My test of 9 Pentium3 notebooks and 1 Pentium2 notebook show me this:
esa(4), ESS Maestro 3 card and ESS Allegro 1 card - don't work after 5.7, needs firmware yds(4), two Yamaha-744 cards - don't work after 5.7, needs firmware maestro(4), ESS Maestro 2E card - don't need firmware, works ok! eso(4), ESS Solo-1, don't need firmware, works ok! some other audio cards, who don't need firmware - works ok! part of audioctl log from OpenBSD 5.8: --- name=ESS Allegro encodings=ulinear:8:1:1,slinear_le:16:2:1,yds_write_codec timeout :175404399:980624640:1935964448*,dec timeout :1970234144:1847616620:1629516911,slots :1818845558:1701601889:1685651466*,timeout! :1717990754:1646293605:1751348335,old firmware file, update please :1952539760:1819287653:1702060389,download microcode failed :1701603681:2660:540701477* --- I think, it's problem with firmware loading for audio subsystem after OpenBSD 5.7.
