[ISSUE] FLAC big file recording freeze on OS X

This problem is common to Nuendo 6 and Cubase 7 on OS X.

I tested long recordings (between 30 and 60 minutes) of eight channel FLAC files at 192 kHz / 24 bit.

When the recording is stopped, Nuendo will freeze for a period equivalent to about half the recording time (around 30 minutes for a 60 min recording). During a typical 30 minutes freeze, the computer hard drive will be read from at maximum speed for the first 25 min (about 200 MB/s on my MacBook Pro with a standard HD and about 340 MB/s on a MBP with a flash drive) and, for the last 5 minutes, the computer will read and write to the HD, hovering between 15 and 20 MB/s. All the while displaying the spinning beach ball.

Steps to reproduce:

  • 1- Create a project with FLAC as file format, 24 bit and, since it’s related to the file size, the highest sample rate your audio interface will allow.
    2- Add a multichannel (maximum eight, the FLAC limit) audio track, record-enable it, start recording (I record white noise from unconnected mic inputs).
    3- Record at least 30 minutes non-stop.
    4- Stop the recording.

Nuendo should then display the spinning beach ball for quite a while…

This was tested with Nuendo 6.0.2/0.3 and Cubase 7.0.2/0.3 on a MacBook Pro with a 500 HD and 16 GB of RAM, a Retina MacBook Pro with a 256 GB flash drive and 8 GB of RAM and a Mac mini with a 1 TB HD and 16 GB of RAM. I tested with a Metric Halo ULN-8 interface and a RME Fireface 800 interface. All with OS 10.8.3.

I’ll just add that I tested again this week-end. I was preparing for a location gig, so I did an empty recording run at 24 bit, 192 kHz, four channel for one hour. When I stopped the recording, the Mac “beachballed” for ten minutes. This is on a MacBook Pro with a PCIe SSD: with a standard HD, this hang would have been much longer.

We’re now at 6.0.6, and nothing about this problem has changed since day one of Nuendo 6…

Please Steinberg, check your implementation of FLAC, there’s a real problem with it.

P.S. And what about WavPack as another format?