USB Audio Issues

USB Device Might Not Be Recognized When Hot-Plugged (4500963)

If a system is booted without the reconfiguration option and no USB keyboard or mouse is connected, USB drivers are not automatically attached. The system will not recognize hot-plugged USB devices.

Workaround: To make the system recognize hot-plugged USB devices, choose one of the following workarounds.

• Add the following line to /etc/system and reboot the system.

  forceload:drv/uhci

• Type the following on a command line.

  # devfsadm -i uhci

For more information see devfsadm(1M).

Audio Applications Might Stop Working After a USB Audio Device Is Hot-Unplugged (4424286)

If you hot-unplug a USB audio device the links to /dev/audio are broken. As a result, some audio applications might not recognize audio devices, including on-board audio. Rebooting the system or hot-plugging the USB audio device has no effect.

Workaround: Perform the following steps after a USB audio device is hot-unplugged.

1. Become superuser.

2. Correct the broken links by typing the following on a command line.

   # rm /dev/audio* # /usr/sbin/devfsadm -c audio

For more information see devfsadm(1M).

USB Speakers Might Not Produce Sound

Third-party USB speakers might not produce sound after the USB driver is attached. Increasing the speaker volume or hot-plugging the device might not have any effect.

Workaround: Powercycle the USB speakers.