User Manual

User's Guide Fireface 800 © RME

Note 2: The DVD player will be synced backwards from the Fireface. This means when using

AutoSync and/or word clock, the playback speed and pitch follows the incoming clock signal.

Note 3: In WinDVD 5 and 6, a channel-seperated 5.1 playback using the Fireface requires a

change in the registry. Start regedit, go to HKEY_CURRENT_USER / Software / InterVideo /

DVD5 (or 6) / AUDIOCHAN, and set its value to 4 (hexadecimal). Additionally select 'Waveout'

as Audio Renderer in the Audio configuration dialog.

Warning: Changes to the registry are done at your own risk. Danger of complete data

loss!

9.4 Low Latency under MME (Buffer Size Adjustment)

Under Windows 95 or 98, the MME buffer size was nothing to worry about. Latencies below 46

ms were not possible. Meanwhile both computers and operating systems have become much

more powerful, and with Windows 2000/XP latencies far lower can be used. SAWStudio and

Sonar allowed to use such low settings from the start. Sequoia was updated in version 5.91,

WaveLab in version 3.04.

In the Settings dialog the DMA buffer size is set with the buttons labeled Buffer Size (La-

tency). This setting is valid for MME, ASIO and GSIF at the same time. Our test computers

allow to use settings down to 48 samples without clicks. Please note that this setting only de-

fines the buffer size of the hardware. The true and effective latency is configured within the

MME application!

Attention: the DMA buffers must not be larger than the application's buffers. This case can

happen unnoticed when using ASIO and MME at the same time (multi-client) and setting

ASIO to 23 ms, while the buffers in the MME application are still set for a lower latency.

Playback will be stuttering and audio will be distorted.

Example: when you set the Fireface to 512 you can't use 128 in any program. But setting the

MME buffer to 128 allows to use 128 and all higher values within the software.

Please also note that this is a 'you're welcome to try' feature. We can't guarantee that you will

be able to use 3 or 6 ms with MME. Simply check out by yourself which lowest setting your

system and software allows. Some motherboards with insufficient PCI bandwidth (especially

VIA based) suffer from crackling at settings below 512. Be sure to set the buffer size to 512 or

higher in such a case (or trash the motherboard…).