[fritsch]

Patches welcome.

[ear_drum]

Setup your dac in alsa config (asound.conf).
Disble your dac in pulseaudio control center.
Start KODI from terminal with "AE_SINK=ALSA kodi"
In system - audio output select your dac..
Check if it is working.

[fritsch]

The OP uses OpenELEC. ALSA is used there by default and no pulseaudio is shipped.

[uomiarz]

Audiolab M-DAC bit perfect test is a utility build in DACs firmware. As I described one of 2 special files is sent to DAC and test procedure says if received data are 100% the same as in files (DAC "knows" what they should be). If data are someway modified or corrupted test fails. I think it's very simple and transparent.

I see no problem with 16/24/32b - bit depth is correctly indicated both for 16b or 24b by DAC with OpenElec 5.0.

M-DAC bit perfect test manual
http://www.google.cz/url?url=http://www....B8hOvb2WCw

bh69 I think this is a key here:

Sending a 16 bit signal via a 32 bit sink format is absolutely lossless - does not harm, does nothing, when the sink now tells: "I wanted a 16 bit signal" - then it is 100% wrong

100% wrong means test failed (no green light if it exists)

Try to contact M-DAC guys and explain how xbmc engine handles 16/24bit files that you use for your test.
Ask what results you may expect.

In your free time read this:
http://xiph.org/~xiphmont/demo/neil-young.html
Article does not address you issue but its definitely good reading

[theFan667]

I'm also using openelec (V5.0.0) with an M-DAC (USB DAC).

I get constant pops through the audio when playing 44.1kHz/16 bit flac files and also with 96kHz/24-bit flac files.

Audio settings i've tried are:
- Audio Lab M-Dac Analog, Best Match
Result: this always gives 48kHz 24bit irrespective of the source encoding
- Audio Lab M-Dac S/PDIF, Best Match, Limit sampling to 192kHz
Result: this gives correct sample rate but is fixed at 24bit irrespective of the source encoding

Both settings give the pops.

There are plenty of forum posts about this over on openelec with no results because the response from those in the know is generally "it's not our problem, it's a Kodi problem".

It used to be that you could add a custom string to the audio settings to tell ALSA to use HW and not HWPLUG and this way the two channel FLAC was not mixed before it was sent to the audio device and everything was fine. This changed at some point when the custom string option disappeared which i'm pretty sure happened when KODI started using Audio Engine and then ActiveAE. From that point on people using USB DACs have had to downgrade back to a version that let you add a custom string.

Please note that i've only just started using Kodi so the above paragraph is what i've extracted from other people's forum posts, not my direct experience. What is my own experience is audio full of pops and no easy way to fix it.

Kodi uses PAPlayer which i'm guessing uses ActiveAE. So if my research is correct then it is ActiveAE causing the problems for those of us with USB DACs. Openelec is a read only squashfs file system so i'm going to instal Kodibuntu and see if i can use an external player that will allow me to configure how audio is output ie use only alsa.

Can anyone see an issue with solving the problem by using an external player? Can anyone suggest a better solution??

I'm a 2-channel person and there are no HDMI cables in the audio chain. As a last resort i'll use an old version of openelec, as a very last resort i'll have to go back to mediaportal/windows.....

Thanks,
Tim

[fritsch]

OE uses plain ALSA nothing else AS does kodibuntu.

[ian-ep]

FWIW, I'm using a Cambridge Audio StreamMagic 2.0 as a USB DAC with Kodi (Openelec 5.0). 44.1 khz FLAC files are identified correctly as 44.1 khz by the DAC - as are 48khz, 96khz and 192khz files. Whether they are 'bit perfect' I couldn't say - but they sound perfectly fine to my ear. No problems whatsoever in that respect.

I've used several other, purportedly 'bit-perfect', players through the same hardware and I certainly can't detect any difference in quality to Kodi's output. Probably because there is none!

Of course, being a little old fashioned, I rely on my ears rather than test equipment to listen to music ... ;-)

Cheers
Ian

[fritsch]

FWIW, I'm using a Cambridge Audio StreamMagic 2.0 as a USB DAC with Kodi (Openelec 5.0). 44.1 khz FLAC files are identified correctly as 44.1 khz by the DAC - as are 48khz, 96khz and 192khz files. Whether they are 'bit perfect' I couldn't say - but they sound perfectly fine to my ear. No problems whatsoever in that respect.

Thank you very much for this comment! Finally someone that trust his ears and not some green lamp.

[bh69]

FWIW, I'm using a Cambridge Audio StreamMagic 2.0 as a USB DAC with Kodi (Openelec 5.0). 44.1 khz FLAC files are identified correctly as 44.1 khz by the DAC - as are 48khz, 96khz and 192khz files.

M-DAC detects correct frequency too (both 44.4 / 96), so I don't undestand what was told above about 32bit

---

Thank you very much for this comment! Finally someone that trust his ears and not some green lamp.

simple "solution" but problem remains somewhere

[fritsch]

96/24 vs. 96/16 or 44.1/16 and so on ...

When you play 96/24 at 96/32 no issue at all - but your DAC's lamp won't be green.


In short: it's not only about the sample rate.

[theFan667]

FWIW, I'm using a Cambridge Audio StreamMagic 2.0 as a USB DAC with Kodi (Openelec 5.0). 44.1 khz FLAC files are identified correctly as 44.1 khz by the DAC - as are 48khz, 96khz and 192khz files. Whether they are 'bit perfect' I couldn't say - but they sound perfectly fine to my ear. No problems whatsoever in that respect.

Could you please share your audio settings within openelec?

I've still got very obvious pops, as do others in the openelec forum.

Thanks.

[fritsch]

Debug Log will tell and after some of those drops: dmesg | pastebinit

I think it's a problem with your usb connection and not Audio Engine related.

[bh69]

When you play 96/24 at 96/32 no issue at all - but your DAC's lamp won't be green.

sorry - I wrote it bad - I wanted to say that DAC tells correctly 44/16 and 96/24 - as source material is - so where is 32bit problem ?

[fritsch]

Read the log of kodi, in fact there are very, very few soundcards on linux that can output S24NE, so we send S32NE there (larger format, lossless conversion from one to the other). And as our intermittant format is 32bit float anyways ...

[bh69]

Read the log of kodi, in fact there are very, very few soundcards on linux that can output S24NE

maybe I'm stupid, but I don't understand still ... I used USB (so no sound card in chain) and M-DAC detected 44/16bit - so it's not sent as 44/32bit ...