iPod touch 3G sound issues

[micr0man]

hello,

I seems recently I have been having issues with my iPod touch. When I listen to music on my iPod though my internal speaker all sound comes out correctly. It will also come out correctly if I connect my computer speakers to the headphone jack. However when I try the headphones themselves connected to the headphone jack the sound comes out horribly. Its hard to explain, more like a decoding problem. It isn't just the music app but all sound coming out of the iPod

Iv'e tried two pairs of headphones, some Sennheiser MX 580's and some Sony's (I don't know the model number). The Sennheiser's have a standard potentiometer volume control but the Sony's are iPod compatible meaning they have a microphone and "remote".

My guess is that the audio driver is not liking the low impedance of the headphones any more but that is a guess. I have tried restoring my iPod twice now but it made no change. I have also noticed that sometimes the Sennheiser's cause erratic bahaviour of the iPod such as opening the Voice Control dialogue, changing songs, repeatedly starting and stopping the music, and sometimes even the iPod thinks iv'e disconnected them. All of this happens if I move the connector

It all used to work, until I set of for a two week holiday in September. This is really starting to annoy my mate so I hope to get it fixed ASAP if possible. There is a high chance i'll have to get a new device as its all so small inside,

Any questions/advice is welcome and I thank you for reading,

Thanks, Dave

 

[Sceadwian]

Have you tested both sets of headphones on a known working devices without problems? I wouldn't rule out both pair of headphones are causing problems, but your theory that it's a problem with the impedance seems solid otherwise, there would be no practical way to repair it. My stepson had a 3rd generation Ipod touch and he had to have it replaced (within the warranty period) due to a bad audio jack, it seems to be a relatively common problem. If your unit isn't within warranty you could possible use a headphone buffer, but this would be pretty impractical for portability.

 

[micr0man]

Thank you very much for the feedback. I just tried my headphones in my computer and they seem to be fine. However I have just noticed putting pressure downwards on the headphone jack the sound comes out fine. This is what really confusing me, because it is not an intermittent sound, its a sound decoding thing. One or two songs sound fine, others are missing some of the layers in a song, and others sound plain weird.

However because pushing the headphone jack downwards makes it work I have tried buying an external jack which along with other things brings out the headphone pins from the iPod dock connector. It is arriving in the post and should be here in October, I will write up my findings when I get the device.

Its out of my warranty period and right now I do not feel like making repairs inside of the iPod, even know it seems well documented so i think this could be the best option. I may try taking it apart though and take a look

Thanks for the suggestion sceadwin,

Dave

 

[alec_t]

All of this happens if I move the connector

The symptoms suggest a bad connection at/in the headphone socket. An intermittent or high resistance connection there will produce distorted or missing sound. Also, if the headphone goes open circuit its inductance will generate a back-emf which might be sufficiently large to cause interference and false triggering of the player functions (track jumping etc).

 

[micr0man]

thanks for your input. Yes I am having the same thoughts. but as far as I am aware the controls should be controlling the iPod via the fourth pin. however as i am using a 3 pin jack on my headphones that connection should be grounded. maybe it is back-emf as you say.

For those interested the device I have brought is a Griffin Navigate, probably a little overkill but hopefully it will be a botch fix. shame I cannot control my iPod from my "remote" any more, or use my microphone as far as I'm aware.

The sound given off I could describe as being a computer generated under water effect. Another idea could be to spray some contact cleaner in there, but do you think that could damage the innards of my iPod too?

again thanks for the help everyone, and greetings from Cyncoed,

Dave

 

[Sceadwian]

If you press down on it and it gets better it's not a decoding issue, it just sounds like one... Seems to me like you have a bad solder joint (same issue my stepson had only one of his channels eventually stopped working altogether) Probably a bad LEAD free solder job.

If you can get it open and you have a heat gun there's a slim chance you could reflow the joints.

 

[micr0man]

yes, there are a lot of videos on how to replace the jack so I may try to put a new one in. It seems pretty hard though so I doubt I will be successful, until I get the guts I think I'll stick to using my Navigate, if that works. My iPod is in need of being upgraded anyway, so won't be the end of the world if I do mess something up.

My other concern is it may not be making contact when pushing the jack, I'm wondering if I am bending a PCB or something making it work in which case it could be any component that has a bad solder joint, who knows, I will have to investigate soon

Thanks for the help again,

Dave

 

[DerStrom8]

You know, it's funny that you should mention this now. I recently had a problem with my headphones and an MP3 player--when they were plugged all the way in the sound was low quality, and only one earbud was working. I pulled the plug out just a little bit and everything worked great. I think it has to do with some of the headphone plug styles and the jack styles. Some of them just aren't all that compatible. I don't know why, but I just wanted to mention that I've been having the same problem.

I hope you can get it figured out soon.
Regards,
Der Strom

 

[micr0man]

Thank you for your input Der. Iv'e spoken to a friend today who has said he has a similar problem too yours, pulling it out a little bit made it work. I tried that today but unfortunately it did not work,

I'm starting to think its either a bad solder joint, a PCB trace has broken, or the headphone jack itself is broken. I would not think the jack is broken as the connectors to touch the headphone jack inside the socket are on a side, but it only works if I push it downwards if that makes sense,

Dave

 

[micr0man]

Just a write-up from the last time,

Due to my very stupid actions iv'e gone further than i wanted. I got really really bored in class so thought what the heck i may as well try taking my iPod apart in class with my fingernail. what a bad idea that was. I ended up cracking my touch screen. After using the plastic tools to get it off I gave up and went for the metal screwdriver. I finally got it off.

At this point I thought I'll never get the screen off again so I may as well my severely replace the back. The new front assembly came in the post today but I am yet to get the back replacement from Hong Kong. Iv'e actually removed all the circuitry from the original back panel so I am ready to move it all back into the new case. Iv'e done some tests and it seems its all working. LCD, WiFi, touch screen, Power, iTunes sync, volume/lock buttons etc etc and it all works.

Having the system in this state means its very fragile but it does also allow me great access to the headphone connector. Moving it around while playing some music in my opinion has diagnosed it with a faulty flexi-PCB / connection to the main logic board. If its the later I may be successful just trying to re-flow the connections with my iron. if it does not work I can try replacing it with a new headphone jack.

However this has caused a dilemma, do I attempt to fix my headphone jack and possibly damage another part of my board or not bother and use the device i am getting in the post soon. (I only have a 30watt iron that cost me about £3 from the local store(I need to upgrade))

On another note it seems my new front panel home button isn't working, but I am trying this disassembled and it looks like a metal panel on the front panel makes connection to the logic board, is this why it isn't working?

All your comments are appreciated, and thanks for reading,

Dave

NB iv'e linked some pictures below of taking it apart