virtualbox.org

I am using VirtualBox with a Windows 7 guest on my Mac OS X host.

When I connect my USB audio device to my Mac, the audio device is listed in the output audio devices on my Mac.
The audio device is listed on my guest but is disabled and I cannot select it.

Unlike the simple eject/unmount that is possible with a harddrive device, I cannot "eject" this audio device.
I found many many topics with solution for USB harddrive but none for USB audio device.

With Parallels (Trial Version) when I connect my USB audio device I am asked where I want to use my USB device.
When I select guest I can use my USB audio device without problem.

I prefer VirtualBox and I am sure that there is a solution to disable this USB audio device from my hosts and use it on my guest.

Thanks for you help.

USB Audio is known to cause issues and VM crash, see #11314 and #11215.
There also several posts on the forum about it, search for "Audio USB"

I have no crash because I cannot select the device in the guest

Create a USB filter for your device, in your VM configuration > USB. There is a USB symbol with a green cirlce, you can then select your sound card and create a filter for it.
Afterwards, simply unplug it, start you VM, plug your sound card, and it should be taken by the guest directly.

Unfortunately after unplug and restart it is always disabled.