Static Noise with USB audio card

[Ivanoo]

Hi,
I need to passthrough a USB audio card to an Ubuntu 18.04 VM. I bought this interface: https://www.amazon.it/gp/product/B01N905VOY/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1.
I tested it on a Windows machine and it works without problems. For some reasons, when the card is in use by the VM, it creates a static noise that I can't remove using alsa or pulseaudio.
I even tried to install Ubuntu 20.04 and 22.04, but the problem still persist.
Am I missing some drivers?

 

[leesteken]

USB passthrough is not very good for high bandwidth or low latency, even with USB3 enabled. Maybe PCI(e) passthrough of a USB controller will work better?
I'm assuming the good test was on WIndows bare metal and not a Windows VM? Otherwise, I can't explain the difference between Windows and Ubuntu except for poor drivers.

 

[Ivanoo]

Hi,
yes the test was on a bare metal windows install.
Can you explain better what you mean with pci passthrough of a usb controller?

 

[leesteken]

Can you explain better what you mean with pci passthrough of a usb controller?

Like a GPU as is often used, you dedicate a PCIe device to the VM and take it away from the Proxmox host (and all other devices in the same IOMMU group). This can be done with any* PCI(e) device like a USB controller (chip). Most devices onboard a PC motherboard are nowadays PCI(e) devices. By passing it through to the VM, the VM will see all the USB devices connected to the (external) ports of the USB controller, instead of the Proxmox host. I don't know how to describe it more. Can you ask more specific questions?
*: In practice the device needs to reset properly and adhere closely to the PCI(e) standards, which is not often and it is trial and error and hit or miss.