Topic: Audio crackles on raspberry pi4 with pianoteq

Good afternoon everyone,

anyone else experience audio crackles with Pianoteq on a raspberry pi?

It only happens at the start of the very first note and a few seconds after the last note is played, it's like the audio engine or soundcard is waking up for the first note and then it switches itself off a few seconds after the last note. it's only really noticeable at higher volumes but there is a very distinct pop or crackle, i also don't think its a performance issue as mostly the cpu usage is around 50-60 percent.
Anyone any ideas please how to fix it?

Re: Audio crackles on raspberry pi4 with pianoteq

Question 1: Have you followed precisely all of the instructions in the Linux readme file?  If not, what is not exactly as described in those instructions?

Re: Audio crackles on raspberry pi4 with pianoteq

hesitz wrote:

Question 1: Have you followed precisely all of the instructions in the Linux readme file?  If not, what is not exactly as described in those instructions?


Hi hesitz,

thanks for the reply, yes i've followed the instructions in the Linux readme and also in Edgar's guide to setting up pt unless I've made a mistake somewhere.

I definitely think it's an issue with the ALSA driver, I also sometimes get a notification from PT that the alsa driver is not available and another app is using it. I also get the pop crackle when I open or close another program like chromium for example.
Anyone experiencing similar issues or have any solutions?

Best,
James

Re: Audio crackles on raspberry pi4 with pianoteq

Enabling the performance governor as described in the README is key so that the CPU runs at maximum frequency and doesn't scale down when you stop playing for a bit, but that doesn't seem to be the problem you're experiencing.

You definitely shouldn't be getting pops and crackles when opening chromium or other applications, are you using the Pi's built-in DAC or an external DAC (like a HAT that sits on top)? I've found the built-in DAC to have rather poor sound quality.

Also you might want to fire up alsamixer and check your ALSA settings.

Re: Audio crackles on raspberry pi4 with pianoteq

jari_42 wrote:

Enabling the performance governor as described in the README is key so that the CPU runs at maximum frequency and doesn't scale down when you stop playing for a bit, but that doesn't seem to be the problem you're experiencing.

You definitely shouldn't be getting pops and crackles when opening chromium or other applications, are you using the Pi's built-in DAC or an external DAC (like a HAT that sits on top)? I've found the built-in DAC to have rather poor sound quality.

Also you might want to fire up alsamixer and check your ALSA settings.


Hi Jari,

thanks so much, yes it was a problem with alsamixer, I use the hifiberry dac pro and when i selected that in alsamixer I could see that there is an automute function and then I disabled it and saved settings, no more annoying crackles/ pops, well just on power down, problem solved, you're a legend Jari

Now to figure out the easiest way to upgrade to PT7.

Cheers,
James

Re: Audio crackles on raspberry pi4 with pianoteq

Hi James,
that's great to hear! No problem at all, happy to have helped

Btw if you purchased Pianoteq recently you'll automatically be upgraded to 7 in your user area.

Re: Audio crackles on raspberry pi4 with pianoteq

jari_42 wrote:

Hi James,
that's great to hear! No problem at all, happy to have helped

Btw if you purchased Pianoteq recently you'll automatically be upgraded to 7 in your user area.

Yes I noticed that, it was a nice surprise

I meant the easiest way to install the upgrade, I have a lot of problems with my pi4, namely could never get the wifi working properly, also could never get it show the correct time and date.

Re: Audio crackles on raspberry pi4 with pianoteq

jamesb5 wrote:

Yes I noticed that, it was a nice surprise

I meant the easiest way to install the upgrade, I have a lot of problems with my pi4, namely could never get the wifi working properly, also could never get it show the correct time and date.

Sorry to hear that, if you can't fix it using the raspi-config tool then the Raspberry Pi Forums are a great resource.

Re: Audio crackles on raspberry pi4 with pianoteq

jamesb5 wrote:
jari_42 wrote:

Hi James,
that's great to hear! No problem at all, happy to have helped

Btw if you purchased Pianoteq recently you'll automatically be upgraded to 7 in your user area.

Yes I noticed that, it was a nice surprise

I meant the easiest way to install the upgrade, I have a lot of problems with my pi4, namely could never get the wifi working properly, also could never get it show the correct time and date.

If I remember correctly, getting working wifi may fix your date/time issue as well (at least if by "no wifi" you also mean "no internet").  I'm not sure what default setting is, but I'm guessing your system is set to automatically get its date/time info from the internet.  Once you have internet connection it will automatically fix date/time.  Can't remember exact settings for that, but I assume it's somewhere in raspi-config.