The NetBSD-current/i386 build is working again. The following commits were made between the last failed build and the successful build:
2016.12.16.22.03.10 christos src/sys/dev/audio.c,v 1.281 2016.12.16.22.10.12 christos src/sys/sys/Makefile,v 1.160 2016.12.16.22.11.04 christos src/distrib/sets/lists/comp/mi,v 1.2081 2016.12.16.22.14.15 christos src/sys/dev/audio.c,v 1.282 Log files can be found at: http://releng.NetBSD.org/b5reports/i386/commits-2016.12.html#2016.12.16.22.14.15