PROBLEMA Ubuntu Virtual Surround 7.1 Usb Headset Turtle Beach Z60

[REZ]

Ciao a tutti!
ho un USB Headset con Virtual surround 7.1 di cui dovrei abilitare tutti e 8 i canali...però essendo USB viene visto da Pulse Audio come normali cuffie stereo...
modificare /etc/pulse/daemon.conf in default-sample-channels = 8 non ha dato risultati
La distro su cui ho il problema è Ubuntu 16.04.2 LTS x86_64 con Desktop Unity...

    name: <alsa_card.usb-Turtle_Beach_Turtle_Beach_Z60_Game_Audio_000000000000-00>
       driver: <module-alsa-card.c>
       owner module: 7
       properties:
          alsa.card = "2"
          alsa.card_name = "Turtle Beach Z60 Game Audio"
          alsa.long_card_name = "Turtle Beach Turtle Beach Z60 Game Audio at usb-0000:00:14.0-7, full speed"
          alsa.driver_name = "snd_usb_audio"
          device.bus_path = "pci-0000:00:14.0-usb-0:7:1.0"
          sysfs.path = "/devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0/sound/card2"
          udev.id = "usb-Turtle_Beach_Turtle_Beach_Z60_Game_Audio_000000000000-00"
          device.bus = "usb"
          device.vendor.id = "10f5"
          device.vendor.name = "Turtle Beach"
          device.product.id = "2129"
          device.product.name = "Turtle Beach Z60 Game Audio"
          device.serial = "Turtle_Beach_Turtle_Beach_Z60_Game_Audio_000000000000"
          device.string = "2"
          device.description = "Turtle Beach Z60 Game Audio"
          module-udev-detect.discovered = "1"
          device.icon_name = "audio-card-usb"
       profiles:
          input:analog-stereo: Stereo analogico input (priority 10, available: unknown)
          input:iec958-stereo: Stereo digitale (IEC958) input (priority 5, available: unknown)
          output:analog-stereo: Stereo analogico output (priority 1000, available: unknown)
          output:analog-stereo+input:analog-stereo: Duplex stereo analogico (priority 1010, available: unknown)
          output:analog-stereo+input:iec958-stereo: Stereo analogico output + Stereo digitale (IEC958) input (priority 1005, available: unknown)
          output:iec958-stereo: Stereo digitale (IEC958) output (priority 500, available: unknown)
          output:iec958-stereo+input:analog-stereo: Stereo digitale (IEC958) output + Stereo analogico input (priority 510, available: unknown)
          output:iec958-stereo+input:iec958-stereo: Duplex stereo digitale (IEC958) (priority 505, available: unknown)
          off: Spento (priority 0, available: unknown)
       active profile: <output:iec958-stereo+input:iec958-stereo>
       sinks:
          alsa_output.usb-Turtle_Beach_Turtle_Beach_Z60_Game_Audio_000000000000-00.iec958-stereo/#1: Turtle Beach Z60 Game Audio Stereo digitale (IEC958)
       sources:
          alsa_output.usb-Turtle_Beach_Turtle_Beach_Z60_Game_Audio_000000000000-00.iec958-stereo.monitor/#1: Monitor of Turtle Beach Z60 Game Audio Stereo digitale (IEC958)
          alsa_input.usb-Turtle_Beach_Turtle_Beach_Z60_Game_Audio_000000000000-00.iec958-stereo/#2: Turtle Beach Z60 Game Audio Stereo digitale (IEC958)