Ravenna Networked Audio Clock Unstable

[cdhoffman]

I'm running a Ravenna Network with two Merging Technologies Horus, two 2013 Mac Pros (10.10.4), a Windows 7 PC, and two ports for laptops. All Ravenna nodes are synchronized by a Dell Powerconnect 2816 managed network switch, loaded up with the custom config file from Merging.

The clock is not stable (or so I suspect), as it becomes "unlocked" according to the Ravenna/CoreAudio Driver page, every few minutes or more. The problem is repeatable on a variety of DAWs both Windows and OSX.

I'm not very savvy with network protocol, my introduction to which has been through Merging Ravenna. Does anyone have prior experience with this or similar (Dante, AVB, etc) issue of clocks not properly synchronizing or staying locked? Perhaps there's a setting on the managed switch that needs to change.

I've tried taking it off wired and wireless internet in hopes that there would be nowhere for the audio packets to go other than the Ravenna Network, but this did not help.

Any ideas would be greatly helpful.

 

[pvision]

I don't know the setup, but which machine provides the master clock?

If the sync is distributed via Ethernet and you have a specific config in the switch I'd assume that is OK. Try looking at the setup of the various nodes to see which clock is designated as master and make sure the rest are slaves

I would not think there is any kind of clock setting on the switch and I don't think network protocol will be the issue. Generally with networks they either work or don't

Nick Froome

 

[Junction]

Make sure all your ports are set to 1G (not 100mbps) and make sure you are using good quality Cat5E or Cat6 cables.

 

[cdhoffman]

I don't know the setup, but which machine provides the master clock?

One is designated as Master, the others are slaves. It supports simultaneous different sample rates, which I suspect uses resampling to achieve this.

Seems like part of the problem is users expecting to be able to run at different sample rates in different applications. Where a normal interface would quickly switch, it seems to take a little longer (10-15sec) with Ravenna. We have a network switch with Merging's config file loaded, but still occasionally see clock dropout.

thanks for your help, I'll update this post if anything new discoveries are made.