Playback problem

Hello all. I am working on an intel mac (intel hd audio). i am running ubuntu studio 9 with parallels desktop. I have both JACK and ARDOUR up and running. however, either one of two cases happen (both regarding the playback in ardour): there is either NO sound even though the tracks are playing (this happens with multi-track projects when I select the PLAYBACK ONLY in the JACK audio settings), OR there is very slowed-down muffled sound (this happens when i choose DUPLEX in the Jack audio settings)…

What could be the problem? / Where have I gone wrong?

Your input would be greatly appreciated!

thanks for the input all.

i forgot to mention, i am not creating new, but opening sessions created and saved from another machine. could this be a reason why each individual track fails to connect to the main out? …the inputs for each track are no longer there, and therefore the track’s relation to the main output has changed…???

Ahha…

If you are opening old sessions, how old are we talking about? There was an issue several versions back in Ardour/Jack that would cause EXACTLY what you are describing with the outputs. This was fixed in recent versions, but sessions made with the old versions still won’t open quite right. The reason is because of the way the ports for the audio hardware were named by Jack, it used to be hardware dependant, so changing between machines with different hardware would mean Ardour couldn’t find ports by those names anymore. More recent versions of Jack instead use a more default “System” scheme for any interface, allowing for MUCH more portability. But because the old Ardour sessions were made before this, they still reference the old hardware based naming scheme, which no longer exists.

   Seablade

i have also tried ARDOUR for OS X but have still had various problems…there it seemed like ardour doesn’t recognize my aggregate device through JACK. when i play anything in ardour, no sound is produced…individual tracks have to manually be connected to the main system outs…maybe you could help me on that issue also…

i also wanted to run blender and kdenlive (which is why i did all the ubuntu with parallels junk)

i have also tried ARDOUR for OS X but have still had various problems.....there it seemed like ardour doesn't recognize my aggregate device through JACK.

It sounds like you are doing something very wrong with Jack to be honest. But in as far as the second part, what you described is more likely to be a bug with Apple’s aggregate device editor. However you would likely have better lnuck getting help asking on IRC sometime in the daytime during EST.

All this being said, I would bet that Jack doesn’t run well in a VM. Jack and Ardour is going to be I/O intensive, an area that VMs are weakest in.

individual tracks have to manually be connected to the main system outs....maybe you could help me on that issue also...

Yes did you by chance uncheck the automatically route track outputs option when you created the session?

    Seablade

“Doing something very wrong with Jack”
Well, that might be the issue in my case too. It would be helpful if you would tell us what the procedure is to convince Ardour and Jack that there’s an output built into my macbook and that, yes, I want to use it.

It seems that Ardour itself is running fine, In the mixer window, I did patch the channels to the master. (How silly that you can patch the master to the master as well. I can tell by the “leds” it’s feedbacking. I know feedbacj is hard to do in software, as functions will call themselves again and ‘explode’, but Ardour did not crash. So Bravo!)

Still, I do not hear anything. Ardour says "[ERROR]: No devices found for driver “NetJACK”. But I can’t click on that to be taken to the right window to resolve this. And I really do not see how I can patch this in the Jack application. The MacOSX systempreferences do show Jack, but do not allow patching it to my built in output.

I am trying Ardour to see if I would advice my students to buy it in stead of protools, but if I run into this problem, they will too.

Well, that might be the issue in my case too. It would be helpful if you would tell us what the procedure is to convince Ardour and Jack that there's an output built into my macbook and that, yes, I want to use it.

That is why I mentioned getting on IRC, as I don’t know off hand, and there is a variety of things I would like to look at that would be much quicker, and honestly a bit easier, over IRC. That being said…

Still, I do not hear anything. Ardour says "[ERROR]: No devices found for driver "NetJACK". But I can't click on that to be taken to the right window to resolve this. And I really do not see how I can patch this in the Jack application. The MacOSX systempreferences do show Jack, but do not allow patching it to my built in output.

This is likely your problem right here, why do you have netjack selected as your driver? This should never be the case unless you are trying to communicate between two computers on a network. On OS X this should be CoreAudio and the appropriate interface/aggregate device selected in the Device settings, and on Linux this should be either ALSA or FreeBOB/FFDAO of course with the appropriate device selected.

This is certainly something you would have had to change yourself at some point, and this is likely your largest problem.

    Seablade

is the samplerate of jack the same as the one of the files you open? if not, that could be the problem.

yes, both are set at a sample rate of 48000

The only way ardour could “slow down” is if there is a sample rate mismatch between the physical soundcard and the rate that Ardour is told it is using. There are multiple layers ( hardware, OS X kernel driver, CoreAudio, Parallels, ALSA, and JACK) involved, but most of those layers are reliable so I’d guess Parallels is the culprit.

If you’re going to run on OS X, why not just run the OS X version of Ardour?