Default hw @startup ----> creating alsa driver ... hw:0|hw:0|

[agentmike]

erverything installed ok.

problem is that Jackd starts with wrong hw.
it says: creating alsa driver ... hw:0|hw:0
while i need Jackd to start with hw1

any way to change this?

[njh]

Looking at the jackd man page, it looks like you have to use the -d hw:1 command line option:
http://manpages.ubuntu.com/manpages/xenial/man1/jackd.1.html
(see the ALSA BACKEND OPTIONS section)

Note that you will have to start jackd yourself before running rotter. It might be a good idea to start rotter with -j to prevent it starting jackd with the wrong parameters.

[agentmike]

Thank you njh!

i already tried it this way. But i encounterd problems. I'm trying to rule out this as the possible reason for my recording problems.

maybe you can help me with this?
problem is that rotter stops recording. filesize doenst increase anymore.
it stops at random moments. i end up with a incomplete recordings.

only error message i see is one about ringbuffer overflow.

[njh]

ringbuffer overflow is usually because it is unable to encode the audio/write to disk fast enough.
(it is capturing audio faster than it can process it - hence running out of buffer space)

What spec of machine are you running on?

[agentmike]

raspberry pi Zero
i tried recording to my NAS and also recording to SD.
Both gives same problem.

Should i try recording to USB stick?

[njh]

I think it is unlikely to be the data transfer rate that is the problem:

44100 Hz * 2 bytes * 2 in mbps = 1.4112 Mbps

Which codec/file format at you using?

Although I imagine that 1 Ghz should be enough to encode MP3 in realtime, it is possible that an ARM CPU doesn't have as good an optimisations as a x86 processor - LAME has assembly based optimisations for MMX / 3DNow! / SSE / SSE2.

Have you tested on a faster machine?

[agentmike]

Not tested yet on a faster machine.
i'm using mp3, but also tested it with WAV
.

i think the problem is with Jack.
it gives xrun errors. wich suggests incorrect (or insufficient) buffer frames settings.

You designed Rotter to auto-start Jack.
Wich parameters does Rotter use to start Jack?
Because i start Jackd separately because of the HW option.

[njh]

Autostart is a feature of the Jack client library - it starts automatically by default - I am not passing any options to jackd.

https://github.com/njh/rotter/blob/master/src/rotter.c#L641