Duplicated device names if IPv6 active, airport not working

[Linwood-F]

I suspect this is some kind of user configuration issue, but am posting it in case.

I have a Ubuntu 16.04 HyperV VM running, and am trying to play from Rhythmbox or VLC to an airport express named Hailun Piano. The device works from a windows PC with iTunes, and appears once in the list.

Running VLC, I see it and my Apple TV twice (but interestingly a receiver only once).

When VLC tries to play to either one, it gives: fast and continuous messages:

[0000000002377338] pulse audio output error: cannot write: Connection terminated
[0000000002377338] pulse audio output error: cannot write: Connection terminated
[0000000002377338] pulse audio output error: cannot write: Connection terminated

all the same.

When using the pulseaudio-module-raop (no 2) module, it also showed up twice (actually once three times), so that is not specific to the '2' version. The 2 version nicely shows IP and port, which look correct (well, IP is correct, no idea about port).

To the extent helpful I ran avahi-browse -atr and pulled out the stuff that looked related (I don't want my whole network posted here). I saw the comments on the 169 network, not sure I understand where they are coming from, but since they are not showing up not sure they matter? Is it the IPv6 that may be duplicating somehow? (My router is handing out IPv6 addresses if requested). The receiver that appears only once does not have an IPv6 address, so I do think that is an issue (not that it got an IPv6 address but it's crossing that up with the IPv4 address and showing the IPv4 twice).

The airport is ONLY hooked up via the wired ethernet port, the wifi is turned off. And as mentioned in iTunes it appears only once.

+   eth0 IPv6 0C5101E9BE5A@Hailun-Piano                     AirTunes Remote Audio local
+   eth0 IPv4 0C5101E9BE5A@Hailun-Piano                     AirTunes Remote Audio local
+   eth0 IPv6 Hailun-Piano                                  Apple AirPort        local
+   eth0 IPv4 Hailun-Piano                                  Apple AirPort        local
+   eth0 IPv6 50-35-10-70.1 Hailun-Piano                    _sleep-proxy._udp    local
+   eth0 IPv4 50-35-10-70.1 Hailun-Piano                    _sleep-proxy._udp    local
=   eth0 IPv6 0C5101E9BE5A@Hailun-Piano                     AirTunes Remote Audio local
   hostname = [Hailun-Piano.local]
   address = [169.254.193.242]
   port = [5000]
   txt = ["sf=0x4" "fv=76800.1" "am=AirPort10,115" "vs=105.1" "tp=TCP,UDP" "vn=65537" "pw=false"  "ss=16" "sr=44100" "da=true" "sv=false" "et=0,4" "cn=0,1" "ch=2" "txtvers=1"]
=   eth0 IPv4 0C5101E9BE5A@Hailun-Piano                     AirTunes Remote Audio local
   hostname = [Hailun-Piano.local]
   address = [169.254.193.242]
   port = [5000]
   txt = ["sf=0x4" "fv=76800.1" "am=AirPort10,115" "vs=105.1" "tp=TCP,UDP" "vn=65537" "pw=false" "ss=16" "sr=44100" "da=true" "sv=false" "et=0,4" "cn=0,1" "ch=2" "txtvers=1"]
=   eth0 IPv6 Hailun-Piano                                  Apple AirPort        local
   hostname = [Hailun-Piano.local]
   address = [169.254.193.242]
   port = [5009]
   txt = ["waMA=0C-51-01-E9-BE-5A,raMA=0C-51-01-EB-8A-B8,raM2=0C-51-01-EB-8A-B9,raSt=3,raNA=0,syFl=0xA8C,syAP=115,syVs=7.6.8,srcv=76800.1,bjSd=9"]
=   eth0 IPv4 Hailun-Piano                                  Apple AirPort        local
   hostname = [Hailun-Piano.local]
   address = [169.254.193.242]
   port = [5009]
   txt = ["waMA=0C-51-01-E9-BE-5A,raMA=0C-51-01-EB-8A-B8,raM2=0C-51-01-EB-8A-B9,raSt=3,raNA=0,syFl=0xA8C,syAP=115,syVs=7.6.8,srcv=76800.1,bjSd=9"]
=   eth0 IPv6 50-35-10-70.1 Hailun-Piano                    _sleep-proxy._udp    local
   hostname = [Hailun-Piano.local]
   address = [169.254.193.242]
   port = [58699]
   txt = []
=   eth0 IPv4 50-35-10-70.1 Hailun-Piano                    _sleep-proxy._udp    local
   hostname = [Hailun-Piano.local]
   address = [169.254.193.242]
   port = [58699]
   txt = []

But my real problem is I can't get any sound, period, and am running out of things to check. I would appreciate any advice.

I also looked at the Airport utility and while I can use manual or DHCP for IPv6, I don't see a setting to turn it off entirely.

[Linwood-F]

Just as a followup I installed Shairport-sync on a raspberry pi which also had a IPv6 address and it shows two entries, one of which has the IPv4 address and one with the IPv6 address (I have not got audio hooked up to it to test at the moment).