Solved KDE sound output

Hello, i cant make sound with the speakers, i have two monitors , one with speakers, and the sound out of here, but i want to make that the sound go out to the speakers, when i try to use kmix and test the sound, go out from the speakers, but when i make anything except the test on kmix the sound go out from the speakers of the monitor, how i can do?
i try some things of the Freebsd Doc, and in firefox, i cant make it works , i try this things
sysctl hw.snd.default_unit= with the numbers 4,5,6,7 and dont work.
i put the output here
cat /dev/sndstat

Installed devices:
pcm0: <NVIDIA (0x0083) (HDMI/DP 8ch)> (play)
pcm1: <NVIDIA (0x0083) (HDMI/DP 8ch)> (play)
pcm2: <NVIDIA (0x0083) (HDMI/DP 8ch)> (play)
pcm3: <NVIDIA (0x0083) (HDMI/DP 8ch)> (play)
pcm4: <Realtek (0x0900) (Rear Analog 5.1/2.0)> (play/rec) default
pcm5: <Realtek (0x0900) (Front Analog)> (play/rec)
pcm6: <Realtek (0x0900) (Internal Digital)> (play)
pcm7: <Realtek (0x0900) (Rear Digital)> (play)
No devices installed from userspace.

dmesg | grep pcm.
pcm0: <NVIDIA (0x0083) (HDMI/DP 8ch)> at nid 4 on hdaa0
pcm1: <NVIDIA (0x0083) (HDMI/DP 8ch)> at nid 5 on hdaa0
pcm2: <NVIDIA (0x0083) (HDMI/DP 8ch)> at nid 6 on hdaa0
pcm3: <NVIDIA (0x0083) (HDMI/DP 8ch)> at nid 7 on hdaa0
pcm4: <Realtek (0x0900) (Rear Analog 5.1/2.0)> at nid 20,22,21 and 24,26 on hdaa1
pcm5: <Realtek (0x0900) (Front Analog)> at nid 27 and 25 on hdaa1
pcm6: <Realtek (0x0900) (Internal Digital)> at nid 17 on hdaa1
pcm7: <Realtek (0x0900) (Rear Digital)> at nid 30 on hdaa1

cat /etc/sysctl.conf
# $FreeBSD: releng/11.0/etc/sysctl.conf 112200 2003-03-13 18:43:50Z mux $
# This file is read when going to multi-user and its contents piped thru
# ``sysctl'' to adjust kernel values. ``man 5 sysctl.conf'' for details.

# Uncomment this to prevent users from seeing information about processes that
# are being run under another UID.

sysctl hw.snd.default_unit=6
and nothing.. if i try
cat filename > /dev/dsp the output is correct, but in firefox i cant reproduce well
what can i do?

when i put a stream in VLC of a radio, the output of the sound is correct, maybe firefox problem??

Found my own solution.

FF was built with audio/pulseaudio option turned on. Instead of recompiling I investigated and found the default sink was set to the hda outputs (HDMI) of the sound card. When I used pacmd to set the default sink to the correct device (you get a list of devices with pacmd list-sinks and the starred sink is the active one) sound started working in FF.

The solution is disable support for audio/pulseaudio in www/firefox when building from ports.