11 Replies Latest reply: Jan 27, 2014 9:07 AM by TNSF
Krutsch Level 1 Level 1 (0 points)

I recently upgraded from a MacBook Pro 17" early 2011 to a MacBook Pro Retina 15" (early 2013).  I have a Drobo and two Seagate 4TB external drives, all connected via Firewire 800.  So, I added a Thunderbolt to Firewire 800 adapter and, it seemed, life was good.


I keep my large iTunes Movie and TV show collection on the Drobo.  Since transitioning to the new MacBook, I have had a number of issue with watching movies on my Apple TV 3.  Randomly, and periodically, the movie appears to be corrupted - the audio track skips/loops and the image is horrible macroblocked, as if the file is damaged.  When I check the movies on the Drobo, opening it with Quicktime on the MBP, it plays just fine at the same spot it appeared damaged on the Apple TV 3.


A second symptom is this: I can no longer re-encode video with Handbrake with the source and target files on the Drobo - it gets some portion of the way through and it just stops, leaving the video partially encoded; again, at random locations/offsets into the video and not the same spot twice.


My initial thought is that connection to the Drobo is dropping out and coming back, on its own, but long enough to cause the above problems.


Is anyone else seeing this issue or something related when using the Thunderbolt to Firewire 800 adapter with large drives?


Thanks, in advance.

MacBook Pro, Mac OS X (10.7.3), Opulence, I Has It...
  • Krutsch Level 1 Level 1 (0 points)

    Well, after a lot of testing, it is definitely a Thunderbolt to Firewire 800 adapter issue with external hard drives.  I have moved files onto a separate USB 3.0 drive and everything works.  Using the external Firewire 800 drives with the Thunderbolt adapter, sporadic issues (i.e. corrupted playback from Apple TV and inability to execute long running programs like Handbrake with the Firewire drives in the mix).


    I have little faith that Apple will ever (a) become aware of or (b) fix these issues, so I will start the process of moving all of my storage over to USB 3.0 devices (and will stay away from Thunderbolt for everything).

  • Frederick Karayan Level 1 Level 1 (5 points)

    I am having the same issue.

    It took me a while but I began to suspect the adapter as well.

    If I restart the computer, the issue will cease, temporarily.

    Or, if I disconnect and reconnect the adapter.


    I hope this is just a defect and not something inherent to the design.

  • Krutsch Level 1 Level 1 (0 points)

    Since then, I've purchased a new adapter and applied a number of Mac OS X updates (I am now on Mavericks), so who knows what was happening, but I seem to be OK now.

  • Frederick Karayan Level 1 Level 1 (5 points)

    Update: I exchanged the Thunderbolt to Firewire adapter and the issue persists. I have a Drobo that I used with my previous system, a PowerMac G5, and never had any issues like this.


    It does not matter what software I use. But at some point video playback will suddenly become garbled. If I start the video from the beginning, sometimes the garbled video will start sooner but never later. A restart temporarily resolves the issue. If I copy the file to the local hard drive the video will play back garbled. This is indeed a very strange issue. The issue behaves like a bandwidth bottleneck.


    I was having this issue prior to upgrading to Mavericks.


    Screen Shot 2013-11-04 at 3.16.25 PM.png


    Fred K

    iMac (Late 2012), 3.4 GHz i7, GTX 680MX, Fusion Drive, 24 GB RAM, Drobo (Firewire via Thunderbolt)

  • petegorilla Level 1 Level 1 (0 points)

    Welcome to the club... I have just recently opened a thread about the same issue, but for me is not data transfer and movie picture and sound, but studio recording with Firewire interface using the same adpter. But the simptoms are the same. stopping, skiping etc....



  • NeilBakker Level 1 Level 1 (0 points)

    I am also having issues with my Dorbo connected via Firewire/Thunderbolt Adapter.  Mine are more with mounting the disk.  About 50% of the time, the disk will not mount when I plug the cable into my brand new (Late 2013) MacBookPro 15".  The only solution I've found is to power cycle the Drobo.  It appears the Drobo does not "wake up" when the cable is plugged in.  This never happened when I plugged the Fireware 800 directly into my old (2009) MacBookPro.


    Preformance seems to have taken a hit as well...


    Very frustrating, as I have 2.24TB of data on my Drobo, and I do not want to spend money on a new, multi disk solution.

  • Krutsch Level 1 Level 1 (0 points)

    Make sure you are not daisy-chaining another FW800 drive with the Drobo.  I used to have a Seagate FW800 3TB drive plugged into the Drobo and I had the same issue you describe above.  After removing the second FW800 drive my problems went away with the Drobo.


    Clearly, starting with Lion and Mountain Lion, there are issues with Mac OS X and chained FW drives - especially via the Thunderbolt to FW800 adapter.


    Frankly, I am finished with both interfaces and have been replacing my drives with USB 3.0, which always works great (and they are much cheaper).

  • hands4 Level 4 Level 4 (2,215 points)

    FYI,  FW connected drives run about 65% the speed of USB 3.0 connected drives.  USB 3.0 drives run about the same speed at TB connected drives (except for SSDs).


    R/W disk speeds:

    USB 3.0 and Thunderbolt about equal at ~110 MB/s

    Firewire about 65% at ~60 to ~70 MB/s

    USB 2.0 about a third at ~35 to ~40 MB/s


    R/W SSD speeds:

    Thunderbolt fastest at ~355 to ~370 MB/s

    USB 3.0 second at ~165 to ~195 MB/s

    Firewire third at ~60 to ~70 MB/s

    USB 2.0 fourth at ~40 MB/s



  • Krutsch Level 1 Level 1 (0 points)

    Exactly... as described the link you provide.  Basically, the interfaces are exceeding the drive performance characteristics, so might as well use USB.  With SSD it does change, but it that really a practical concern?  Who is going to pay big bucks for large, external SSDs?

  • Frederick Karayan Level 1 Level 1 (5 points)


    I erased and installed 10.9 and restored from AirPort Time Capsule backup, no change.

    What has me totally baffled about this issue is that when the problems arises, a restart will resolve it. I don't know what triggers the behavior. There is nothing else other than a restart that will resolve it (granted, I have not gone through every process running in Activity Monitor either :-)

  • TNSF Level 1 Level 1 (0 points)

    I have the exact same problem.  Brand new iMac, Apple Thunderbolt to Firewire adaptor, Drobo.  The only thing that consistenly fixes the issue for me is restarting my Drobo, which takes a long time.  Not only is this inconvenient, but i'm worried about the impact of constantly rebooting Drobo by unplugging it.  This can't be a good thing.