Ardour reports "Wrong port-type" error and freezes

Installation & Configuration Linux
#1

Here we are again ole luvin’, the economy’s crumbling and the world is just a few steps away from being at war again, dontcha just love it. To make things worse, my beloved and trusted Ardour 8.12 starts to behave strange again, that is, what I percieve as strange, ignorant meatbag that I am.

I’ve been wanting to bring up the issue for some time now. As soon as I import a WAV, particularly drum tracks created with Hydrogen, I get the flashing red point in the right upper corner and the respective notification says:

2026-04-18T10:16:36 [ERROR]: BackendPort::connect (): wrong port-type trying to connect ardour:x-virtual-keyboard and ardour:Monitor/audio_out 1

2026-04-18T10:16:36 [ERROR]: BackendPort::connect (): wrong port-type trying to connect ardour:x-virtual-keyboard and ardour:Monitor/audio_out 2

Before that, I don’t know exactly when it changed, the text used to be something like this:

2025-11-15T08:07:51 [ERROR]: ardour::connect: Invalid Source port: (ardour:XYZ 1/audio_out 1)
2025-11-15T08:07:51 [ERROR]: ardour::connect: Invalid Source port: (ardour:XYZ 1 1 1/audio_out 1)
2025-11-15T08:07:51 [ERROR]: ardour::connect: Invalid Source port: (ardour:XYZ1 1/audio_out 1)
2025-11-15T08:07:51 [ERROR]: ardour::connect: Invalid Source port: (ardour:XYZ 1/audio_out 1)
2025-11-15T08:07:51 [ERROR]: ardour::connect: Invalid Source port: (XYZ/audio_out 1)
2025-11-15T08:07:51 [ERROR]: ardour::connect: Invalid Source port: (ardour:Audio 1/audio_out 2)
2025-11-15T08:07:51 [ERROR]: ardour::connect: Invalid Source port: (ardour:XYZ 1/audio_out 2)

XYZ being a placeholder for the actual filename.

Until today, I simply ignored the red flash and the ERROR message, because Aurdour seemed to work fine and I was too impatient to look into the issue, I just wanted to record music. But by now it seems that the program keeps chewing on the wrong parameters and a loop builds up which eventually becomes too much for the CPU. TOP shows 196% (Dual Core CPU, Debian 11) consumation by the Ardour GUI, and the remaining 4% just allow for changing to the prompt and kill the process. Try that with one of microsoft’s abominations by the way, good luck.

I would be most obliged if somebody would be as kind as to brief me on which parameters to set in order to prevent this from happening, thanks for your attention and your valuable time. I’m on my last leg recording the next song which I’d like to upload in the Made With Ardour department, naturally.

Keep on rockin’ in the free world!

Sincerely,

Fineweather

1 Like
#2

What settings do you use in the Audio/MIDI setup window?

#3

The ones which appeared to be the safest.

Audio Device: Alsa

In - and output device: either the DI or USB Microphone, activated by alsamixer

Sample rate: 48 Khz

Buffer Size: 512 samples, which has been a good compromise between stabilty and low latency so far

#4

Your USB microphone also has outputs?
I am not sure what device you mean by “the DI,” does it have the same number of inputs and outputs as the USB microphone?

#5

DI = Digital Interface, the analogue/digital converter, in my case a Zoom U-22. Connected to the computer via USB plug, like the USB Microphone, as the name says. No further connections.

I am convinced that those two can be ruled out as possible sources for the problem. Ardour never complained about a single track that was recorded with either one of them, they worked A-Ok out of the box from day one. Like I said in my original post, the issue appears to be with imported WAVs.

Anyway, why do you ask, what’s the idea?

#6

I just started Ardour and I get the same message again:

2026-04-19T07:18:09 [ERROR]: BackendPort::connect (): wrong port-type trying to connect ardour:x-virtual-keyboard and ardour:Monitor/audio_out 1
2026-04-19T07:18:09 [ERROR]: BackendPort::connect (): wrong port-type trying to connect ardour:x-virtual-keyboard and ardour:Monitor/audio_out 2

This is something new I’m certain. Never had that before.