Takashi Sakamoto wrote:

I do not understand techinical details, but the sound was

...

perfect even with 192kHz/24bit audio using libffado.

Ditto. libffado works with such broken stream by ignoring its packet index. I guess that you've continued to use your device with uns-ynchronized state for several years because no one reports it.

Well, one reason I believed I was doing fine with my Orpheus is one of the experiments I did in November 2010.

------------------------------------------------------------------------- I copied a 44.1kHz/16bit sound file into a USB memory, and played it on PS3.

The optical output (SPDIF) of PS3 is fed into the optical input of Orpheus, and the data is captured using ffado and jackd.

Two files, the original and the captured, are compared and showed perfect match.

https://spinorlab.wordpress.com/2015/04/25/orpheus-and-bit-perfect/ (see https://spinorlab.files.wordpress.com/2015/04/orpheusbitperfect.jpg) -------------------------------------------------------------------------

I know I should have compared by not only capturing by Orpheus but playing by Orpheus, but I saved my effort assuming the reverse way should also be OK.

(Actually, I did not expect any negative results. Was I too optimistic?)

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Therefore, I still can not believe I am experiencing packet losses (without noticing).

I mean not with juju+libffado+jackd. I really don't know what is happening with snd-bebob.

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So if it's only a

...

#define TIMER_SOMETHING value_anything type of things...

I cannot understand what you mean.

Never mind. I am not a very technical person anyway.

I just thought if it is due to a VERY STRICT timeout checking policy, relaxing the value of timeout might help.

Unless fully understanding specifications about your device, you cannot make firm statement about it, I think. The drivers installed in Windows or OS X can set the synchronization when plugging-in.

You are correct! (See the item 8 below.)

I did some experiment today, although I am not sure if it has any technical meaning.

--------------- My PC runnging on Windows 7 --------------- 1. Run Control Panel, and set Sync Source to PC DAW. 2. Play music with Audacity -> O.K. -> Stop music. 3. Kill Control panel. 4. Set Orpheus to Stand-by Mode 5. Remove Firewire Cable 6. Recover from Stand-by Mode 7. Connect Firewire Cable 8. Run Control Panel, and Sync Source now reads Local,

/*** this is not what I expected, but it is so. ***/

so set Sync Source to PC DAW again. 9. Play music with Audacity -> O.K. -> Keep playing 10. Kill Control Panel. -> Music still playing O.K. -> Stop Music 11. Set Orpheus to Stand-by Mode 12. Remove Firewire Cable

--------------- Reboot My PC to start Linux --------------- 13. Recover from Stand-by Mode 14. Connect Firewire Cable 15. Enter the following CLIs.

% dmesg [ 21.838971] r8169 0000:02:00.0 eth0: link down [ 24.281647] r8169 0000:02:00.0 eth0: link up [ 281.110728] irq_handler: 36 callbacks suppressed [ 281.110737] firewire_ohci 0000:08:00.0: isochronous cycle inconsistent [ 281.612586] firewire_core 0000:08:00.0: created device fw1: GUID 00119800010001f9, S400 [ 281.612747] firewire_core 0000:08:00.0: phy config: new root=ffc1, gap_count=5

% ls -l /proc/asound lrwxrwxrwx 1 root root 5 Apr 25 21:55 Orpheus -> card3

% cat /proc/asound/card3/firewire/clock Sampling rate: 44100 Clock Source: External (MSU-dest: 7)

% aplay -D plughw:3,0 test.wav Playing WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo aplay: set_params:1297: Unable to install hw params: ACCESS: RW_INTERLEAVED FORMAT: S16_LE SUBFORMAT: STD SAMPLE_BITS: 16 FRAME_BITS: 32 CHANNELS: 2 RATE: 44100 PERIOD_TIME: (46439 46440) PERIOD_SIZE: 2048 PERIOD_BYTES: 8192 PERIODS: 4 BUFFER_TIME: (185759 185760) BUFFER_SIZE: 8192 BUFFER_BYTES: 32768 TICK_TIME: 0

% dmesg [ 21.838971] r8169 0000:02:00.0 eth0: link down [ 24.281647] r8169 0000:02:00.0 eth0: link up [ 281.110728] irq_handler: 36 callbacks suppressed [ 281.110737] firewire_ohci 0000:08:00.0: isochronous cycle inconsistent [ 281.612586] firewire_core 0000:08:00.0: created device fw1: GUID 00119800010001f9, S400 [ 281.612747] firewire_core 0000:08:00.0: phy config: new root=ffc1, gap_count=5

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Regards, Mike Ood