virtualbox.org

Hi all,
I am running Ubuntu 11.04 as guest OS in a Mac OS X host system. Runs very well, also the sound is working (Intel HD Audio -> Coreaudio).
Now I would like to route some audio from my Mac to the guest OS and back to the standard audio output of my Mac. Therefore I installed Jack OS X, the Mac version of the jack sound server. If I go into the routing, I can see a entry called "VirtualBoxVM" and I can route audio. However, this entry is only in the "send" OR in the "receive" side of the routing, but I was expecting it to be in both sides as the VM can receive and send audio data.
Asking in the Jack OS X group gave the answer that this is a property of the applications, thus VirtualBox does not seem to support bidirectional audio?
Anyone having a solution for this issue?
Best regards,
Martin

You set up a Jack client on OSX, set up Jack Server on the Guest, send audio to the Guest and the Guest will then play it using the Host CoreAudio audio system. Strange way to play sound, but fine. You could also install PulseAudio instead, it's better supported in Linux these days (I rarely see Jack and I've even seen apps remote support for it).

You must also know the difference of an audio server serving remote playback capabilities, sending audio to a remote audio server and actual playback through the hardware.

Thanks for your reply. Still, things did not become very clear for me. (Maybe I didn't explain well, or I just don't get it.)

I am running a Jack Server on the OS X Host (not the guest) and are currently using PulseAudio on the Guest (Ubuntu). I now want to configure the Jack Server to route the audio data from a Host application to the Virtual Machine, and back to the Jack Server (or alternatively directly to the System output).

Is there anything I can do to have the VirtualBoxVM in both receive and send ports of the Jack Server?
As far as I understand I do not need any remote service that transmits the audio data over network for this. I just need bidirectional routing via Jack to and from the virtual machine, right?

You still seem to fail the concept of it all. You cannot not send audio to another system without a network connection. What you're trying to do here is nothing more than send audio to another system and route it back. Thus this is not a VB question and should not be discussed here, as it's off-topic. The only link here is that you're not using a separate physical machine to achieve your goal, but a VM instead. Same concept applies.

OK, we are dealing with audio over network then. VirtualBox obviously supplies this, as it let's me adjust the audio setting and I can play sound on the VM which I hear in my host system. When using Jack OS X, I see the VM as an application and I can route the audio to the VM. I just don't see why unidirectional audio is supported and bidirectional is not.
Funny that the guys from Jack say this is an application related topic and the VM guys tell me that it is not.
Cheers anyways.

I'm telling you the same, it's application related, but over the network. If you can already send audio from your Mac to the Guest using Jack, then you got what you want I guess. The VM will then play it, in which VB will use the Host audio system (coreaudio) to play the sound. If you would mute sound on the Host, the Guest won't make a sound either.

I've read some more about Jack and see one fundamental problem in your idea. Jack is meant as a system to route audio from one application to another. This does not work with VB, because even though VB is an application, the Guest system it runs is not. You have to use a network solution. Jack does offer one, but PulseAudio might be easier.

Just now (after my holidays) I am seeing your reply, Sasquatch. Thanks again for your time to reply.

In the sound preferences of the host system (OS X) the JackRouter can be selected for both Input and Output individually. The idea is to use iTunes on the Host for audio playback and loop it to the VB and back. Unfortunately iTunes does not allow to set its output to the JackRouter, as it always uses the main output. So I set iTunes --> JackRouter --> VB.

The VB (like iTunes) also returns its audio output to the main output, which is the JackRouter. So I need bi-directional audio routing (which does not seem to work unfortunately).

Sasquatch wrote:I'm telling you the same, it's application related, but over the network. If you can already send audio from your Mac to the Guest using Jack, then you got what you want I guess. The VM will then play it, in which VB will use the Host audio system (coreaudio) to play the sound. If you would mute sound on the Host, the Guest won't make a sound either.

Sound very reasonable, but only works with audio applications on the host system that talk to the JackRouter as non-default device (so that the Host audio system is a "real" output).

Sasquatch wrote:I've read some more about Jack and see one fundamental problem in your idea. Jack is meant as a system to route audio from one application to another. This does not work with VB, because even though VB is an application, the Guest system it runs is not. You have to use a network solution. Jack does offer one, but PulseAudio might be easier.

I will read more about audio via network, that seems to be the golden key and will work on both virtual and real machines. However, the application I want to use on the guest system (brutefir) is also limited to certain audio protocols, with Jack being one of the supported ones. So NetJack could be an option.
Cheers...