Memory access noise on Clip+

[Gunbuster]

Hello folks,

First I know this is a long known issue

http://www.rockbox.org/tracker/11907
http://forums.rockbox.org/index.php?topic=28150.0
http://www.hydrogenaudio.org/forums/index.php?showtopic=86306

But I found out that downgrading to 3.7 completely eradicated the issue for me, it may be still there but I can't ear it even if I try to !
Playing with different versions it seems the issue appeared since 3.8.1

Here is two record of what happen when I skip track rapidly and the buffer need to be refilled :

Clip+ on 3.13 : https://www.dropbox.com/s/y4t4c4xc3o663o5/clip%2B%20noise%203.13.wav
Clip+ on 3.7 : https://www.dropbox.com/s/ue58txa3lsbcaij/clip%2B%20noise%203.7.wav

The constant background noise is because of my bad line in, as you can hear the access noise present from the rockbox 3.13 record is completely absent from the 3.7 one.

I heave two memory cards, a 32gb class 4 from Sandisk and a 32gb class 10 from Transcend and the issue is the same for both of them, but the pitch of the hum vary depending of the album I play (may be related to the position of the file in the card.)

Now I can't help but wonder if the noise/flickering screen issue on the Fuze+ is related to this one. On the Fuze+ it's less annoying because the buffer is much bigger thus it needs to be refilled less frequently.

[saratoga]

Since this only happens on a small number of devices I think you'll be on your own figuring out a solution. Going to be hard for other people to help without access to your player.

That said I'd be surprised if older versions of Rockbox sound different.

[Gunbuster]

Hi saratoga, thank you for your answer.

I don't want to sound rude to you but I'm not sure denying/overlooking the problem exist is the way to go.

The problem exist and I proved that something changed that broken rockbox at least on my device since 3.8.1

The thing is I bought a Fuze+ considering that like you said, only a small portion of devices maybe affected, so I thought I would have more luck with another device...  but I'm a little baffled to encounter another issue that look very similar.

Not Rockbox fault though and I know this will be difficult to resolve if, again like you said, only a small number of devices is affected.

Then again I thought that bringing a new clew on this issue might revive some attention to it, maybe it wasn't that new after all  :'(

Would be nice if, since I'm not alone to have this issue, other peoples try the same thing as I did and test with an older version to see how it goes.

[saratoga]

Noise on SD access is common to a large number of sandisk players and has been for years now. No idea about the fuze plus but it wouldn't shock me.

[[Saint]]

I don't want to sound rude to you but I'm not sure denying/overlooking the problem exist is the way to go.

At no point did anyone do so.

Saratoga did not deny the fact that this issue exists, his second post goes on to acknowledge that on some devices this is a well known issue. All that was said was that this problem only seems to occur on some players, and that without having physical access to a player that presents the issue it is unlikely anyone will be able to do anything about it. These are truths.

He also stated that he would be surprised if prior revisions lessened the issue (and, I would be, too), but this again is not saying that it does not in fact do so, or that you are not experiencing the issue.


[Saint]

[Gunbuster]

Hi Saint,

Please consider that English is not my native language, and also the fact that it's hard to tell someone who have far more knowledge that I will ever have that I have strong convictions he may be wrong to assume things this way, without sounding like a total ass.

Again based on my experience, the records I provided, and more importantly my ears, I think you and saratoga are both wrong.

But I know you have reasons to assume things like this and it will be hard to convince you both.

I myself would be surprised if one could state the fact that my device is not affected by 3.7 and 3.8 but it is with all subsequent versions starting from 3.8.1 is a total accident and nothing can be learn from this.

I would be glad if I could help the community by lending my device to a developer.

[[Saint]]

Gunbuster,

I am aware of the fact that many people that use these forums do not speak English natively, and although I do try to adjust my language to suit this, it may be the case that misunderstandings occur. I understand this.

I want to make totally clear to you that no one is denying that you are experiencing issues with audible memory access. This issue has been reported multiple times, across different devices, it is not uncommon. It is a known issue.

No one is saying you are not experiencing this.

What is being said, is that it is basically impossible for a developer to do anything about this unless they have a device that shows the issue. Presently, to my understanding, no one does.

Another thing that was said is that it would be surprising if this issue presented itself in one version of Rockbox, but not another. I agreed with this. It is important to understand that this is not saying that you are incorrect or mistaken, it is simply saying it is surprising.

No one is saying you are incorrect.

Your findings are helpful, and appreciated, and no one said that it wouldn't potentially lead to the cause of the issue. What is being said, however, is that it is not something that can be reproduced on demand (many devices do not show this problem at all), which makes the issue incredibly difficult to fix unless a developer has a device that shows this issue. Recordings of the issue happening are great, but not useful for the purpose of solving the issue. The only thing the recordings would solve is doubt the issue exists, but there is no doubt of this.

I understand this must be frustrating for you, but it seems you think that we are denying the issue exists. We are not.


[Saint]

[Gunbuster]

I acknowledge my wording was unfortunate.

It was not my intention to make a fuss about this, and I apologize for all the misunderstandings.

Thank you for taking your time to explain me why it can't be solved that easily even though I'm pretty confident about my finding.

If a developer is somewhat interested about this issue, please let me know, I will send him my devices right away.

[404_user_not_found]

I tried to test noise difference from 3.13 and 3.7 in my Clip+ 8 GB, but I can't downgrade to 3.7 due the error "No Partition Found. Insert USB Cable and fix".

[Gunbuster]

That's weird, is everything ok when you revert back to 3.13 ? How is 3.8 then ?

[saratoga]

Your player maybe too new a hardware revision to support such an old build.

[Gunbuster]

So I bought a brand new clip+ from Amazon, I rockbox it right out of the box with the latest stable (3.13) play a song and I can hear the "BZzzzzZZZBvbzZZZzzz" of the buffer being filled up so I'm a little astonished to say the least...

... But I'm not done yet, so I put 3.7 on the clip+ and guess what, it's dead silent now !

Tbh I can still hear a very little tiny sound that I couldn't hear with my 2 years old refurbished device, but it's still like 100 times quieter than the newer firmwares, I could never record that sound like I did with the 3.13 release.

At this point it can't be an accident, something definitely changed that broke rockbox at least on the clip+ since the 3.8.1 release.

[gevaerts]

If I read this thread correctly, you said it was also silent with 3.8, but not with 3.8.1?

If so, http://git.rockbox.org/?p=rockbox.git;a=commit;h=d1fdb485b12676dc99db29ee9f9900c9c752c124 is almost certainly involved. If the commit message is correct and doesn't omit anything, that means it's one of

• http://git.rockbox.org/?p=rockbox.git;a=commit;h=1675e98925fb976314c199116e37ed81e98ca530
• http://git.rockbox.org/?p=rockbox.git;a=commit;h=3d3c0c51ec4e30a961cab311c17ddeab5c5c6a18
• http://git.rockbox.org/?p=rockbox.git;a=commit;h=fc0ad4c01ec938e11fbcfcb8d6a517bf50922a35
• http://git.rockbox.org/?p=rockbox.git;a=commit;h=d3c796d20e4bd8e15f18a0dac2e9c4283df5740b
• http://git.rockbox.org/?p=rockbox.git;a=commit;h=2543340bf4ee69f9005b14e5fb335187125a5e94
• http://git.rockbox.org/?p=rockbox.git;a=commit;h=6512f0fb522144b121c38c53ea780c939b6e027c
• http://git.rockbox.org/?p=rockbox.git;a=commit;h=502e9e97b6c91999e6d0d92802e59d13d8ffc9de
• http://git.rockbox.org/?p=rockbox.git;a=commit;h=86c4ec7277ac1c2a130a9ac1a3500c8360af5c7e
• http://git.rockbox.org/?p=rockbox.git;a=commit;h=7d74fdec020d1f54f0cab318c595d34dd2dc1a0c
• http://git.rockbox.org/?p=rockbox.git;a=commit;h=5c4c691cd3465c3cbca83581aa079648fa2d8d04
• http://git.rockbox.org/?p=rockbox.git;a=commit;h=8351a1aa9db98bab1f66274ee7b7e33839a31c60
• http://git.rockbox.org/?p=rockbox.git;a=commit;h=eab630a1e1463be244118613537f6a04d290f5e0

Now, I'm not an sd specialist and I don't have a clip+, so I can't verify much of this, but someone who knows the ams sd driver should be able to work with that information

[Gunbuster]

Yes I can certify with 100% accuracy that both of my devices are not affected with 3.7 and 3.8, well it is to a certain extent,  it appears that it can vary from devices to devices as I can still hear a tiny sound with the new device that I couldn't with the old one (it may still be present though, I just can't hear it)

But it's not even close to what I can hear with newer firmwares since 3.8.1.

Thank you for your research on this issue and I hope it can help someone resolving it.

I wish I could help more.

[bertrik]

IMO, the most likely candidates are (most suspicious first):
* http://git.rockbox.org/?p=rockbox.git;a=commit;h=5c4c691cd3465c3cbca83581aa079648fa2d8d04
* http://git.rockbox.org/?p=rockbox.git;a=commit;h=8351a1aa9db98bab1f66274ee7b7e33839a31c60
* http://git.rockbox.org/?p=rockbox.git;a=commit;h=7d74fdec020d1f54f0cab318c595d34dd2dc1a0c
* http://git.rockbox.org/?p=rockbox.git;a=commit;h=eab630a1e1463be244118613537f6a04d290f5e0

Can you try this rockbox build (it has 5c4c691cd3465c3cbca83581aa079648fa2d8d04 reverted)?
https://docs.google.com/file/d/0ByItZAj1MynOUHpndW0yTmMydVk/edit?usp=sharing
Select File/Download on the top left, save the rockbox.zip file and unzip over your existing installation on the clip+, such that it overwrites the files in <your-clip+-drive>:/.rockbox