Mic input works fine but silent on pre and post

Hi, I’m using Ardour 2.5 on Mint 6.0. I have my mic plugged in and I can see the meter in the editor mixer responding correctly to sound, but only when it’s set to “input”. When it’s on “pre” or “post” it’s just silent, even with the volume up all the way. Of course this means I can’t record, even though Ardour is clearly getting sound. Any ideas? Thanks.

Open the mixer and choose the track/ channel you are going to record on.
On top of the chanel there is an box labeled input and if you press it you can select the input from your soundcard 1-2, 3-4, …
Select the record button and adjust the level. Choose “play” to start the recording.

Leave the other one in post mode. Hope it helps.


Thanks for the advice, but I’ve got the inputs set correctly. It’s just that in the mixer editor on the left, when the mode button below the meter is set to “input” I see the meter responding to sound. But when it’s set to “pre” or “post”, the meter shows no sound, and number at the top goes to “-inf”. As I understand it, this means sound is getting to Ardour through Jack correctly, and that track is set to the right input, but when it’s supposed to be processed by the pre-fader functions, I get nothing out the other end.

And what do you know, now there’s another error - When I hit record, a log window pops up continually displaying “[ERROR]: MMC: cannot send command 8”. The log window takes control away from the main window, so I can’t stop either of them, and I have to xkill the while thing.

Any help is greatly appreciated.

I can’t comment on the input level issue, but the MMC error can be avoided by going to Options and within that menu, disabling “Send MMC”.
This issue has been fixed - 2.5 is now consider a “quite old” release. I never really understand why so many users get stuck with such old versions, but you’re not the first and probably will not be the last.

They get stuck with it because it is likely still the most recent ‘approved’ release in many distributions repositiories sadly. But I know you are aware of that of course.


Upgrade Ardour and see if your issue was fixed in one of the many releases since 2.5

But to be hoenst if I am understanding you correctly, your issue is with how the metering acts, not with audio signal getting into or out of Ardour. Have you tried to actually record the sound yet? I wuld imagine, but haven’t confirmed, that the Pre and Post metering may be taking the data from specific places that might not account for processing an input signal in the way you are expecting. This is because in most cases people would rather record the input signal dry, and apply the processing after they have a clean input in the DAW.

If I misunderstood and your issue is with more than just the metering of the signal, does it record when set to ‘Input’ as you would expect?


I may be wrong but that sounds like a monitoring thing, not necessarily a wrong ardour behavior.

If you have a track armed for recording, with an OK source plugged to its input port (mic, whatever), you will see the “input” meter react to the incoming volume of the source. “Input” is automatically selected for the metering when you arm for recording.

The pre or post volume metering will also react but only if ardour does the monitoring (software monitoring). If ardour is configured to let the hardware do the monitoring, the input volume will not reach the fader (pre and a fortiori post), that’s just a by design consequence, not a bug.

Once you have recorded something, ardour will switch automatically to “post” metering when you play it back. This is because ardour reads out audio from disk and processes it, so the audio reaches the fader in this case.

I forgot to add: if you really want to have pre or post fader receiving the input signal from say your guitar while you play, set ardour to do software monitoring. If you do that, you can use ardour as a realtime effect box :slight_smile:

If you do have hardware monitoring, there’s not so much point in letting ardour do the software monitoring but in this case, you won’t have the input signal reaching the fader, so no software effects in ardour in realtime.

Honestly, this is much better to use hardware monitoring. You can in this way use a big jack latency (depends on your h/w of course, some route the incoming signal directly to the analog outputs for monitoring so you have virtually 0 latency). You can also fiddle with software effects after you have recorded. Since ardour is non destructive in normal track mode, you will keep your recorded material intact. Software effects during playback can be modified at will without modifying the data read out from disk. And to nail this further, most studios run with a big latency, you want safe operations when recording. The monbitoring is done by hardware to give a feel that you hear stuff you’re actually playing instantaneously. Mixing, arranging, etc, is done post-recording :wink:

Thanks a lot! And yes, 2.5 was what fell out of the Ubuntu repos. I’ll have to do 2.8 from source and get back to you.

before you try compiling 2.8 from source, play with the monitoring in ardour 2.5 according to what I said above. As far as I remember, 2.5 was fine with respect to monitoring (software and hardware). So remember:

when ardour does the monitoring (software mon.) : the audio signal reaches the track fader
when monitoring is not done by ardour (so-called hardware mon.), the audio signal will not reach the track fader

tip: if instead of a track, you use a bus, it does not matter: the audio will reach the bus fader regardless of the monitoring type set up in ardour. But in this case, you won’t record anything since a bus is a “simple” audio route (not connected to disk stream).