828mkII Losing Sync: Possible Solution

[Steven Bell]

Symptom: the slave unit's sample rate indicator flashes and the audio goes silent and/or bleeps are produced.

The main thing I am doing different is to wait until the computer is fully booted up before adding the MOTU units, the firewire controller or the external hard drive.

I used to have all of the external devices on and connected BEFORE booting up the computer.

Details:

1. Turn the computer, MOTU's and External hard drive off. Disconnect the firewire interface card.
2. Configure external hard drive to use USB2.0 port instead of sharing firewire with the MOTU units
3. Use a UniBrain PCMIA card rather than the one that came with your laptop
4. Keep the hard drive off and the PCMIA card OFF until the computer is re-booted
5. Turn on the external hard drive and wait for it to be recognized
6. Insert the UniBrain PCMIA firewire card
7. Turn on the master MOTU and wait for it to boot up
8. Turn on the slave MOTU

For some reason this seemed to make the system much more stable.

My SONAR 5.0.1 test project is 16 tracks of 44100/24 audio of which 14 are input monitored and are routed to two buses. 14 of the 16 tracks also have TrackPlug effects inserted. The Main bus has Compression, EQ and Reverb inserted. The monitor bus has EQ.

The MOTU Audio panel has 192 as the size of the DMA buffer.
SONAR is using WDM drivers and the latency is at 4.4ms

The UniBrain card has a place for each of the MOTU firewire cables so they don't have to be daisy chained.

I applied the Microsoft patch and set the SidSpeed to (2) since this interface is FW400, not FW800.

I do not know which of these things is significant and which are not.