User Manual

User's Guide Digiface USB © RME

8. Operation and Usage

8.1 Playback

In the audio application being used, Digiface USB must be selected as output device. It can

often be found in the Options, Preferences or Settings menus, as Playback Device, Audio De-

vices, Audio etc.

Increasing the number and/or size of audio buffers may prevent the audio signal from breaking

up, but also increases latency i.e. output is delayed.

Note

: Since Vista the audio application can no longer control the sample rate under WDM.

Therefore the driver of the Digiface USB includes a way to set the sample rate globally for all

WDM devices, found within the Settings dialog. See chapter 8.1.

8.2 DVD-Playback (AC-3/DTS)

AC-3 / DTS

Popular DVD software players can send their audio data stream to any AC-3/DTS capable re-

ceiver via the Digiface USB.

The sample rate must be set to 48 kHz in the Digiface USB Settings dialog, or the software

will only playback a stereo 2-channel downmix via SPDIF.

In some cases the Digiface USB output device has to be selected in >Control Panel / Sound /

Playback< and be set as Default, or the software will not recognize it.

The DVD software's audio properties now show the options 'SPDIF Out' or similar. When select-

ing it, the software will transfer the non-decoded digital multi-channel data stream to the Digi-

face USB SPDIF output.

Warning

: This 'SPDIF' signal sounds like chopped noise at highest level.

Multichannel

PowerDVD and WinDVD can also operate as software decoder, sending a DVD's multichannel

data stream directly to the analog and digital outputs of the Digiface USB. For this to work se-

lect the WDM playback device ’Loudspeaker’ of the Digiface USB in >Control Panel/ Sound/

Playback < as ‘Standard’. Additionally the loudspeaker setup, found under >Configuration<, has

to be changed from Stereo to 5.1 Surround.

PowerDVD's and WinDVD's audio properties now list several multichannel modes. If one of

these is selected, the software sends the decoded analog multichannel data to the Digiface

USB. On some software it is not necessary to select the Loudspeaker in the Sound panel.