EMU_A_CHAN_FXRT2
emu_wrptr(sc, ch, EMU_A_CHAN_FXRT2, 0x3f3f3f3f);
emu_wrptr(sc, v->vnum, EMU_A_CHAN_FXRT2, v->fxrt2);
emu_wrptr(sc, v->vnum, EMU_A_CHAN_FXRT2, (v->routing[7] << 24) |
emu_wrptr(sc, ch, EMU_A_CHAN_FXRT2, 0x3f3f3f3f);