[alsa-devel] M-audio Audiophile Firewire

[Takashi Sakamoto]

On Oct 27 2016 04:25, Pap Peti wrote:
> I think my things still belongs to the 'alsa-devel' topic, because I use 
> the 'ffado-mixer' only to 'turn on' my audio input(s)/output(s)
> 
> I added my username to the "audio" anyway, and already I wont noticed 
> noise (but sometimes the audio 'stream(?)' stuck a ~half second when I 
> listen music and e.g.: meanwhile run a long file copy, or come some 
> sound from the browser. I think its a 'multi-threaded' problem, and/or 
> different audio sampling rate in same time.
> 
> So I use to make live records, and do some electric tracks too, but I 
> dont feel I need Jack, because ALSA also can work with low latency (at 
> least in the Tracktion). And - strange - but I feel on this platform the 
> sound quality better than on Windows (with Win10 and the latest Win7 
> 64bit drivers).

If you need "sham" latency value, using libffado stuff is suitable to
your aim.

In a point of packet streaming protocol for IEC 61883-1/6 and interrupt
interval of OHCI 1394 context, ALSA bebob driver has minimum value for
PCM frames in one buffer period. Currently tt's 5msec. In detail, see
comment of corresponding code:
http://git.kernel.org/cgit/linux/kernel/git/tiwai/sound.git/tree/sound/firewire/amdtp-stream.c#n140

Jackd with firewire backend just displays value convenient to users,
although it's not reasonable in a technical point.


Well, about the noise you heard, I can't re-generate the issue. So we
could judge it depending on environment. Do you explain more details?
Which application you use? What OHCI 1394 controller you use? And so on.

> My main problem already only;
> 
> After when I turn off the soundcard and/or the laptop, I need to start 
> again the ffado-mixer to turning on the channels (default: every channel 
> muted, or inactive). I'd appreciate some stuff that resolves the basic 
> settings, I only need the 1/2 sreaming out and 1/2 analog input. Thats all.
> 
> (sometimes when I restart the system and the soundcard still on power 
> (external ps) the settings are retained)

This is not supported in ALSA bebob driver because it can be implemented
in user land. Please use ffado-dbus-server/ffado-mixer or
libhinawa/hinawa-utils.


Regards

Takashi Sakamoto