Chromecast Audio cannot stream audio

Looks like I need to activate "Multicast forwarding" and IGMP to get the Chromecast Audio to work properly.
Found a sophos guide how to activate Multicast forwarding, but my webadmin does not look and is not the
same as in the guide.. I do not have the features or menu choices as in the guide :(

Can somebody please help me! All help is appreciated!

This is the guide I found:
https://www.sophos.com/en-us/support/knowledgebase/123135.aspx
I do not have a "System -> Routing -> Static Routing" menu choice..
I only have "Interfaces & Routing -> Static routing" but I do not have the "Enable Multicast Forwarding" option..
Hell I am tired of this firewall right now :P

Does anybody has a chromecast audio and can tell if you experience any problem with it? I can't be the only one with a sophos UTM and a chromecast audio on this forum? :P 
Right now the chromecast audio is a piece of garbage for me because of the firewall.. 
I do not understand the Multicast routing menu.. I read the sophos guide but the guides is pretty useless because it does not explain what everything is.
What is a "Rendezvous point router"? Do I have to set up some kind of external router or what does it mean? The guides just point out the obvious, 
"type in the hostname for.." and does not explain what the hell it is at all :P

Frustrated.. sorry.. :P

I've got the same issue with chromecast audio and UTM 9. Has anyone been able to get their chromecast audio to stream from Pandora or Spotify reliably? Would appreciate incite from anyone to config settings.

Hi!
Looks like nobody has a solution on this one. I have googled it and found absolutely nothing about this. Looks like nobody has the combination Chromecast audio and Sophos UTM. 
I am currently looking to replace my sophos with pfsense instead to see if it works better. I really hate to not get things to work.

Hello,

I also have this issue. I first thought that it was the Chromecast. But recently discovered that it was the UTM. I have not found a solution yet. I'm thinking on making the Chromecast completely open to the internet, so an any- any rule from internet to the Chromecast. Will let you know if this works.

I have already tried to open the firewall so my entire network can communicate on every port out to internet (but not in).
Did not work, unfortunately. 

Ok, If I'm not mistaken is this what the Chromcast should do. It should make a connection with Spotify directly, so without your mobile in between. So have you also tried to open up the firewall form externall to internall? I think Spotify can't connect with the Chromecast for some strange reason. I will also openup a support ticket at google.

Hi, I found a topic on the chromecast support form. Someone had the same issue with Chromecast audio - Spotify - UTM 9 and he solved it. Unfortunately he did not give the solution. So I created a new post in the hope he will answer and give us the solution.

Exactly, the stream goes directly to the chromecast when casting the audio.
No I have not opened (or made any portfortforward) to the chromecast audio from outside the firewall. This should not be neccessary, I think. (I have not found any information regarding which ports are used anyway)
For example works Spotify connect from my yamaha receiver and it is pretty much the same concept I think.
From my mobile phone I choose to play the stream on my receiver and via spotify connect it plays, and 
I have not opened any ports in the firewall. I can see a constant connection to spotify from my receiver so I think the receiver connects
to spotify connect, not the other way around.

I think the problem is Multicast forwarding and/or IGMP but I don't know how to set up this in the UTM. I can't say these sections are not self explained.

I have also found the thread where somebody had problem with the chromecast audio and the UTM and solved it, but sadly he didn't tell how. 
It should be illegal not to say how something was solved when writing in the forums ;) 

It is interestering that I almost can get it to work. The chromecast shows up in the network and in spotify I can choose to stream the content to the chromecast.
When choosing the chromecast the chromecast makes a beep and the phone are trying to connect, without luck tough.
But the chromecast get some information that a stream is incoming, but can't play or can't reach the stream somehow..

Update on this issue: 
I tried to stream music from player.spotify.com in chrome web browser from my macbook pro (connected via the same accesspoint as my phone and chromecast audio).
This was completely successfull! In other words, I am able to stream from a tab (via the cast extension in chrome) to the chromecast audio, without setting up anything in my firewall regarding this. 
Bad thing I can still not initiate a stream from my ipad or my android phone. Does not see the difference? All devices are connected wirelessly.. 

Can somebody else try and see if this approach also works for you? (Stream a tab from chrome via cast extension. For example login to spotify from the web browser and stream that tab in chrome)