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Support and General Use => Audio Playback, Database and Playlists => Topic started by: kingsmedley on February 17, 2011, 01:44:46 PM

Title: Random lock-ups during playback (Ipod mini)
Post by: kingsmedley on February 17, 2011, 01:44:46 PM
A few months back, I upgraded to version 3.7.1. Since then, I have been experiencing random while playing music or podcasts. When the unit locks it usually goes silent, but sometimes there is a peculiar static noise. I am able to reboot the unit and it goes back to normal, though sometimes it takes a few tries to get the reboot to work.

I am using an Apple Ipod mini (1st gen). I replaced the internal HD with an 8MB flash card last year, and ran that config for a long time (a year or more) under 3.5.1 without trouble.

Before any one asks. the reason I changed to the new version is because I was hoping I could play back podcasts in AAC format. I can live without this, just thought I'd try it. Just for the record, the new version couldn't do it either.

Reinstalling 3.7.1 does not eliminate the problem, and I cannot replicate it at will.
Title: Re: Random lock-ups during playback (Ipod mini)
Post by: Chronon on February 17, 2011, 01:56:50 PM
I expect there's something about the podcasts that prevents their playback, as AAC-LC should play in real time.

I'm not sure what is causing the behavior that you're seeing.  It would be good to exclude file system errors (though I don't think they would explain such random lock-ups -- I would expect failures to be correlated with playing certain files, etc.).  You can also try installing a current build to see if you see the same behavior. 

Does the original firmware suffer lockups too?
Title: Re: Random lock-ups during playback (Ipod mini)
Post by: Buschel on February 17, 2011, 02:01:44 PM
In fact we have several bug reports that describe lock-ups, also describing static noise. There have been bugfixes and rework in the area of buffering. It's not known whether this fixes the issues.
Good to know that this does not happen with v3.5.1
Title: Re: Random lock-ups during playback (Ipod mini)
Post by: Chronon on February 17, 2011, 02:13:30 PM
In fact we have several bug reports that describe lock-ups, also describing static noise.
Is FS#11764 one of these?  (Though it seems to be correlated with seeking in that one.)
Quote
There have been bugfixes and rework in the area of buffering. It's not known whether this fixes the issues.
Good to know that this does not happen with v3.5.1
So, it should be helpful for kingsmedley to see if the same problems exist with a current build.
Title: Re: Random lock-ups during playback (Ipod mini)
Post by: Buschel on February 17, 2011, 02:24:56 PM
Yes, FS#11764 is one of these.

And yes, re-testing is helpful. But right now there are some thoughts that these issues might be connected with ATA-DMA which was enabled with v3.6.
Title: Re: Random lock-ups during playback (Ipod mini)
Post by: gbl08ma on February 17, 2011, 02:31:24 PM
Just to confirm, the AAC files you're trying to play are not protected with any kind of DRM, are they? If they are, I'm sorry to tell you, but Rockbox doesn't support DRM (nor it will do).


I also have occasional lockups with my iPod Nano 2G. I'm using a custom build, but last time I checked it also happened with the official current builds. It may either keep playing for hours without stopping, or stop after playing 30 seconds of music. It's random and doesn't have anything to do with a specific file(s).
The issue started when I had my music collection in MP3 and now that I converted it to OGG the issue still persists; however lately (past two weeks or so) it's less common - I usually update my source code checkout once or more per day and make a custom build (with patches) out of it, but as I said, the issue also happened last time I checked (nearly a month ago) with official builds. It even seemed to happen more frequently with official build, but perhaps it's just me.

Usually when Rockbox hangs it's simple as stopping playback (sometimes with a noticeable "click" sound) and becoming silent, then I go checking and the screen or the backlight (if it was turned off) don't turn on, or if Rockbox hangs with the screen on, it's possible to see that nothing on the screen moves, and it doesn't answer the keypad presses or scrollwheel.
It also happened two or three times that Rockbox [Rockbox just hang again, please wait while I reboot :D] stopped playback to start making a noisy noise (any way to explain it better?), like when you have a FM radio tuned in a frequency where there is no broadcast, only interference.
More recently, I've detected a third type of hang: I'm using Rockbox (changing of track, browsing the options, the files, the database, or just looking at the WPS), and suddenly it stops responding (menu selector doesn't move, I can't select anything and scrolling lines stop to scroll), but playback continues for two or three seconds and after that time period it, after sometimes doing the "click" noise on the speakers, stops playback.

In other words, I don't know very much about how the "stacks" we see on the debug menu work, but if it's possible to have one of them stopping responding independently from others, then IMO when Rockbox hangs the "main" and "scroll" (and possibility others) stacks stop responding, and the "audio" stack keeps working for two seconds until it hangs too possibly because "codec" and "buffering" stop working too.

Finally, to get Rockbox running again I do a reset with Menu+Select and after it boots up it's good to go (and then it's random again, it may hang 30 seconds after to 10 hours later).

[Rockbox hang again while I was looking at the "Stack usage" debug screen... the screen and backlight are on but unfortunately there doesn't seem to be much this dead screen can tell me about these hangs... rebooting again]

As you can see, either I'm very dumb to explain this issue briefly, or this is definitely hard to explain.

EDIT: oh well, it seems there are already bug reports in the tracker for this... here's my testimonial anyways.
EDI 2: it seems I forgot to say that when the screen is on, sometimes it's possible to read "Invalid instruction at 00FF00FF00" on the screen, where 00FF00FF00 is some hexadecimal code (probably the position in memory where the faulty code was, IDK) that always changes; most of the times Rockbox just keeps on showing what was on the screen before.
Title: Re: Random lock-ups during playback (Ipod mini)
Post by: kingsmedley on February 17, 2011, 08:43:29 PM
RE: AAC files: The files in question are very large and with no DRM. These are podcasts typically running between 1.5 to 2 hours in length. I did read somewhere regarding AAC compatibility that larger files can cause Rockbox to choke, so I sort of expected it to fail.

@gbl08ma: What your are describing sounds very similar to my issue, though I have not been interacting with it when it fails so I can't comment on loss of response vs. audio cut off.

Sometimes the ipod is silent when it locks up, but if you leave it in it's locked state you can get static coming and going later on, sometimes hours later.
Title: Re: Random lock-ups during playback (Ipod mini)
Post by: kingsmedley on March 07, 2011, 09:49:06 AM
An update:

I upgraded to version 3.8 last week. So far I have only locked up twice - both times this morning, but it isn't the same. I get the following message:

Data abort at 00044444 (0)

I had to reboot the ipod to continue, and then it happened again just a minute or two later, exact same message, and the same song. I don't think the mp3 is corrupted because I was able to continue playing after the first time, locking up at a different point later.

However, my battery was VERY low. In fact at first I had assumed the battery finally died, so I was surprised to look down and see the screen had lit up. I am recharging now, so I'll try to continue with the same song later and see if it crashes on a full charge too.
Title: Re: Random lock-ups during playback (Ipod mini)
Post by: Chronon on March 07, 2011, 12:49:28 PM
kingsmedley, can you try a current build instead?  It looks like a fix was committed on March 1 -- after the release of 3.8.
http://svn.rockbox.org/viewvc.cgi?view=rev;revision=29476
Title: Re: Random lock-ups during playback (Ipod mini)
Post by: kingsmedley on March 10, 2011, 12:00:16 PM
To follow up my last post - Same song did not crash on full charge, replayed three times with no issues. I haven't run the battery down again to see if the issue repeats.

kingsmedley, can you try a current build instead?  It looks like a fix was committed on March 1 -- after the release of 3.8.
http://svn.rockbox.org/viewvc.cgi?view=rev;revision=29476

My luck with current builds hasn't been that great, I usually end up with more problems that way. So I just wait for the stable releases. But if this problem comes back again soon, I'll give it a try.

Meanwhile, my original problem hasn't come back on the new load. Used to see it at least 3 - 4 times a week. I'm not ready to declare it cured yet, but I'm feeling pretty good about it right now.