Recording works fine in Audacity. When I try to record in with renoise, I have crackling (as if there isn’t enough CPU). I have Realtime setup, Im using ALSA. I cant get jack to work with renoise for some reason.
Please post the info of that script
Does playback work without issues? What interface are you using?
1 Like
I thought the issue was just with my laptop but my desktop has the same problem. I’m using the same usb soundcard.
perl ./realTimeConfigQuickScan.pl
== GUI-enabled checks ==
Checking if you are root… no - good
Checking filesystem ‘noatime’ parameter… 4.15.0 kernel - good
(relatime is default since 2.6.30)
Checking CPU Governors… CPU 0: ‘ondemand’ CPU 1: ‘ondemand’ CPU 10: ‘ondemand’ CPU 11: ‘ondemand’ CPU 2: ‘ondemand’ CPU 3: ‘ondemand’ CPU 4: ‘ondemand’ CPU 5: ‘ondemand’ CPU 6: ‘ondemand’ CPU 7: ‘ondemand’ CPU 8: ‘ondemand’ CPU 9: ‘ondemand’ - not good
Set CPU Governors to ‘performance’ with ‘cpupower frequency-set -g performance’ or ‘cpufreq-set -c -g performance’ (Debian/Ubuntu)
See also: cpu frequency scaling - LinuxMusicians
Checking swappiness… 60 - not good
** vm.swappiness is larger than 10
set it with ‘/sbin/sysctl -w vm.swappiness=10’
See also: Configuration 'quickscan' - Page 3 - LinuxMusicians
Checking for resource-intensive background processes… none found - good
Checking checking sysctl inotify max_user_watches… < 524288 - not good
increase max_user_watches by adding ‘fs.inotify.max_user_watches = 524288’ to /etc/sysctl.conf and rebooting
For more information, see System configuration [Linux-Sound]
Checking access to the high precision event timer… not readable - not good
/dev/hpet found, but not readable.
make /dev/hpet readable by the ‘audio’ group
For more information, see System configuration [Linux-Sound]
Checking access to the real-time clock… not readable - not good
/dev/rtc found, but not readable.
make /dev/rtc readable by the ‘audio’ group
For more information, see System configuration [Linux-Sound]
Checking whether you’re in the ‘audio’ group… yes - good
Checking for multiple ‘audio’ groups… no - good
Checking the ability to prioritize processes with chrt… yes - good
Checking kernel support for high resolution timers… found - good
Kernel with Real-Time Preemption… not found - not good
Kernel without real-time capabilities found
For more information, see System configuration [Linux-Sound]
Checking if kernel system timer is high-resolution… found - good
Checking kernel support for tickless timer… found - good
== Other checks ==
Checking filesystem types… ok.
** Set $SOUND_CARD_IRQ to the IRQ of your soundcard to enable more checks.
Find your sound card’s IRQ by looking at ‘/proc/interrupts’ and lspci.
Oxygenfad: Could I suggest that you find out why you can’t get jack to work and be able to record via jack and see if you still get crackling.
There are some parts that can be optimized on your system:
- you should set the CPU Governors to performance
- swapping isn’t configured yet
- sysctl inotify max_user_watches can be ignored
- access to the real-time clock should be configured
- RT kernel is not needed, should also work good without one
Another thing you can test: Try booting from an AVLinux USB stick. It’s already configured for realtime audio. If it is not working there I guess your interface is broken or not compatible with Linux: