Hi,

I have been trying to find a similar issue in this forum but have not been successful.

Issue: Fairly random dropout with Fireface 800

Hardware:
- MacBook Pro 2010 with OWC SSD as Main drive, 8 GB RAM, 10.6.8
- DTVideolabs PlaybackPro Plus 3.3.0 for Playback, which uses Quicktime-Foundation
- Fireface800 connected via 2m Firewire 800 Cable, no Daisy chaining
- Activity Monitor was relaxed in terms of available RAM (4+ GB), Hard drive activity (around 40 MB/s), CPU load (displaying 60% for the Playback Pro Process).

Setup:
- First 4 analog output channels of the FF connected to the mixer
- Using Final Cut to create Quicktime-Files with Apple ProRes that contain 4 discrete audio tracks at 48k sample rate
- Fireface Mixer was open in background (so I could watch the meters) during rehearsal and show - so I could see the dropout already happening on the meter bar in the mixer

Random things:
- Fireface Settings does not change the setting when I select 48k over 44.1k - it always "jumps" back to 44.1
- Setup played fine a whole day of rehearsal, but the dropouts started during the first video in the show ;(
- After a reboot the dropouts continued during the 2nd show after which we swapped the card to a USB one with only 2 channels.
- The dropout occurred on files with only 2 audio channels being present (not all files were using 4 channels) but also on files with 4 audio channels.
- All 2 / 4 channels were affected when the dropouts occurred
- The dropout started with low repetition and the repetitions increased (1st dropout of about half a second after 1min, 2nd dropout about 10s later, dropout following closer after each other, finally no audio)
- the dropout usually started about 1min into the video. When starting another video or restarting the video, it would play fine for some time but then the dropouts would occur again.
- None of the lights on the front of the FF changed state during the dropouts - which means there should not be a firewire issue like a broken cable, host failure etc.
- There was no motion during the dropouts - no hard kicking sub bass or any movement of the laptops / cables etc.
- The dropout also occurred on the meter bar of the Fireface Mixer - a bit like the dropout was "in the file" which it wasn't as the dropouts occurred at different times of the files and also the exact same files worked fine during a whole day of rehearsals.
- After swapping the FF for a 2 channel USB external sound card (that has worked with Playback Pro+ lots of times before) everything worked flawless for the rest of the shows.

I will re-create the setup in the coming days to reproduce the issue using the same Fireface and the same Mac.

Any ideas / help appreciated
Tobi