I have tried adapting and importing the USB audio driver from kernel 3.0.1 into kernel 5.0.2, because otherwise I cannot easily downgrade the system to 3.0.1. The result is that the Hercules P32 DJ audio interface is not even detected, although the kernel module apparently loads fine. I have also tested the same audio interface on another computer which runs kernel 4.8.8 and the latest ALSA library: it works fine. >From the latter, I take that: - the bug is not due to the ALSA library; - the bug is not due to a faulty hardware / firmware. Next, I would like to upgrade to kernel 5.0.2 on the second machine mentioned above. I have no other ideas... I can still try to file a bug against the core USB kernel driver, although it is very generic, I don't really know how to file it and what information to provide apart from the audio interface and USB hub make and model. Guido > Il 22 marzo 2019 alle 16.05 Guido Trentalancia <guido@xxxxxxxxxxxxxxxx> ha scritto: > > > I suppose the Fedora 29 kernels are included in the range I tested as broken, i.e. 4.12 -- 5.0. > > So, there is something triggering it on my system and not the other, maybe the USB system as pointed out by Clemens. > > I'll make some research on the two USB systems... > > I would also like to try USB Audio driver from kernel 3.0.1. > > What else do you suggest? > > Guido > > Il 22 marzo 2019 15:58:23 CET, Takashi Iwai <tiwai@xxxxxxx> ha scritto: > >On Fri, 22 Mar 2019 15:54:03 +0100, > >Guido Trentalancia wrote: > >> > >> As already explained, I have tested the following kernels: > >> > >> - kernel 5.0.2 -----> BROKEN > >> - kernel 4.17.10 --> BROKEN > >> - kernel 4.12.9 ---> BROKEN > >> > >> So, it's been around for very long. > >> > >> What do you suggest doing? > > > >But which kernel is used for another user who can use without the > >problem? I suppose they use the recent kernel with Fedora? > > > >> I have found reports on the web about similar problems (with other > >audio > >> interfaces) with kernels>3.0.0. > > > >Such a regression should have been reported earlier, otherwise it > >becomes more and more difficult to catch up... > > > > > >thanks, > > > >Takashi > > > > > >> Regards, > >> > >> Guido > >> > >> Il 22 marzo 2019 15:47:36 CET, Takashi Iwai <tiwai@xxxxxxx> ha > >scritto: > >> > >> On Fri, 22 Mar 2019 14:44:48 +0100, > >> Guido Trentalancia wrote: > >> > >> Hello Takashi. > >> > >> I have carried out the test that you proposed... > >> > >> My reply follows your quoted text. > >> > >> On Fri, 22/03/2019 at 11.12 +0100, Takashi Iwai wrote: > >> On Fri, 22 Mar 2019 11:04:01 +0100, > >> Guido Trentalancia wrote: > >> > >> Hello Takashi, > >> > >> I am using the latest version of everything, > >including kernel and > >> ALSA > >> userspace library / tools. > >> > >> The other user has exactly the same hardware and has > >tested same > >> firmware > >> (both 1.36 and latest > >> 1.46), but with Fedora 29 and it is working. > >> > >> Perhaps Fedora 29 has a different version of the > >ALSA library, I > >> will find > >> out, try to downgrade, test again and report back. > >> > >> Yes, that'd be really helpful. If aligning the software > >doesn't fix > >> the issue, it's either because of the hardware or the > >difference of > >> usage patterns. > >> > >> I have tested exactly the same ALSA userspace library and > >plugins > >> distributed by Fedora 29 and it does NOT work ! > >> > >> As already explained, the usage pattern is exactly the same > >between me > >> and the user which is not experiencing this severe problem. > >> > >> Also, the hardware is the same: Hercules P32 DJ (with > >exactly the same > >> firmware version 1.46 which is the latest). > >> > >> So, the conclusion is that it must be a kernel bug ! I was > >expecting > >> this, as already pointed out in previous messages. > >> > >> Did you test the > >> very same kernel, too? Without that confirmation, no > >> one can conclude that at all... > >> > >> If the kernel makes difference, you can try identify which kernel > >> version starts showing the problem, and at best, do git > >bisection. > >> > >> thanks, > >> > >> Takashi > >> > >> Can you please help me fix this bug since you wrote the > >driver and/or > >> are maintaining it ? > >> > >> Thanks, > >> > >> Guido > >> > >> thanks, > >> > >> Takashi > >> > >> Guido > >> > >> Il 22 marzo 2019 10:53:11 CET, Takashi Iwai > ><tiwai@xxxxxxx> ha > >> scritto: > >> > >> On Fri, 22 Mar 2019 > >> 10:17:17 +0100, > >> Guido Trentalancia wrote: > >> > >> It cannot be a firmware bug, as you say, > >because: > >> > >> - it does NOT happen on Windows! > >> > >> It doesn't mean that the device behaves > >correctly as > >> advertised. > >> > >> - it does NOT even always happen on Linux: > >other users > >> (with different kernel > >> / ALSA library) are not experiencing the > >same problem; > >> - it happens with several firmware > >versions, including the > >> latest one (1.36 > >> and 1.46). > >> > >> So it is either a bug in ALSA kernel > >driver, USB sound > >> driver (more likely) or > >> ALSA library. > >> > >> Now, you are in charge of the USB sound > >driver, can you > >> please double check?? > >> > >> If it doesn't happen for other users with the > >very same device, > >> you'd > >> need to identify what's the difference > >> between your case and > >> others. > >> For example, if the difference of alsa-lib > >matters, you can try > >> the > >> very same condition. > >> > >> This kind of bug can't be easily debugged > >without the actual > >> hardware, unfortunately. > >> > >> Takashi > >> > >> Regards, > >> > >> Guido > >> > >> Il 22 marzo 2019 09:55:52 CET, Takashi Iwai > ><tiwai@xxxxxxx > >> ha scritto: > >> > >> On Thu, 21 Mar 2019 23:27:46 +0100, > >> Guido Trentalancia wrote: > >> > >> I wonder if this might be due to a > >bug in the > >> "USB Audio Driver for Alsa"? > >> > >> > >https://git.kernel.org/pub/scm/linux/kernel/git/t > >> orvalds/linux.git/tree/sound/usb > >> > >> > >https://git.kernel.org/pub/scm/linux/kernel/git/t > >> iwai/sound.git/tree/sound/usb > >> > >> More likely a buggy firmware of your > >USB audio device > >> :) > >> > >> From the driver implementation POV, > >both audio and > >> MIDI devices are > >> handled by individual endpoints, hence > >they shouldn't > >> conflict. > >> > >> Or another possibility would be some > >USB host side > >> issue like the > >> bandwidth. But > >> it's a MIDI stream that is very low > >data rate, so this > >> sounds also unlikely... > >> > >> thanks, > >> > >> Takashi > >> > >> Guido > >> > >> On the 20th of March 2019 at > >21.47 Guido > >> Trentalancia > >> <guido@xxxxxxxxxxxxxxxx wrote: > >> > >> Hello. > >> > >> I am hitting a very serious > >bug (ALSA kernel > >> driver or ALSA library) > >> when using the Hercules P32 DJ > >audio > >> interface. > >> > >> The sound is severely > >distorted during MIDI > >> transfers. > >> > >> To reproduce: > >> > >> + start playing something in > >a first > >> console: > >> > >> console1# AUDIODEV=hw:2,0 play > >audio.wav > >> > >> + the audio plays fine > >> > >> + now start "amidi" in a > >second console > >> while the above track is still > >> playing > >> > >> console2# > >> amidi -p hw:2,0,0 -d > >> > >> + the sound is now severely > >distorted > >> (basically noise, with some > >> hard- > >> to-distinguish features > >resembling the > >> original track) until "amidi" > >> is > >> interrupted ! > >> > >> > _______________________________________________ > Alsa-devel mailing list > Alsa-devel@xxxxxxxxxxxxxxxx > https://mailman.alsa-project.org/mailman/listinfo/alsa-devel _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
