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      08-16-2013, 02:10 PM   #1
sipman
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can't play more than one song from android via aux input

Bought my car used and it has an ipod kit in it. But it also has the factory Aux in.

In the past, i though the Aux in was taken by the ipod, but since discovered it isn't.

But when I hook up my Galaxy S3, and hit play, it plays through the phone's speakers. If I unplug the line from the aux input and plug it back in, it plays though the car's speakers.
But once that song is over, the phone stops. If I select the next track, the phone stops. If I press play, I have to pull the cord out again, and reinstall it. So if I want to listen to 10 songs, I have to press play 10 times and do the plug trick over and over.

Does this sound like a car issue or an android issue?
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      08-17-2013, 09:57 AM   #2
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Samsung Galaxy S3 issue

So my research revealed it's a problem with the phone.

Apparently, and I apologize for my layman's terminology here, the phone doesn't see any resistance, therefore doesn't think a headphone is attached.

So the solution that worked for me (YMMV), was to cut my adapter cord and solder two resistors between the hots (Left and Right) and Ground. This tells the phone that there is a level of resistance between the positive and negative of each channel like the phone would find when sending a current through the magnetic coils of a headset.

I took a stab in the dark at using radioshack's carbon film resistors in a 10 ohm and 1/4 watt variety.
My rationale was that older headphones operate in the 8ohm realm, and newer ones are 16 or 32 ohm. so 10 is in the middle of the two. My wattage was just because. No rationale there except that I couldn't imagine a ton of wattage goes through these wires anyways.

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      08-17-2013, 10:12 AM   #3
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The problem I see with this is that your volume through the car would be horrible. All the power that should be delivered to the AUX input would now be dissipated by the resistors and very little power actually gets transmitted to the car's AUX input.
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      08-17-2013, 04:10 PM   #4
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Brilliant solution.
I just measured a couple sets of ear buds and they're 17-18Ω.
If your level is too low, you should be able to go up to at least 20Ω.
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      08-17-2013, 05:52 PM   #5
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That's really odd, does the AUX disappear from the radio, or does your phone just stop playing?

With my car if I try to charge and listen to my iPhone at the same time it causes a ground loop issue and the radio wont see the AUX input for a moment.
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      08-18-2013, 04:28 AM   #6
sipman
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I thought the same thing but after testing it there's no problem with volume. My feeling is that the cell phone won't switch the output to the headphone cord unless it measures resistance. So plugging the cord into only the phone and it sees resistance in each loop.
But once I've plugged it into the aux in, it becomes path of least resistance. Which I'm guessing is through the head unit's electronics. Which is of such low impedance that the phone thinks its an open loop and switches back to it's internal speaker(s) before this mod.
I played a couple of songs and no immediate problems. I'll try and feel the resistors through the insulation after a long drive to see if they are warm, which would definitely indicate they are handling current. But unfortunately, I can't say that if they are cold that they aren't stealing juice like you suggest. But like I said above, it seems to have no effect on volume.

If anyone wants to test the hypothesis, try putting a resistor on one loop only. If the left plays louder than the right, or vice versa, then we'll know this to be the truth. I'm thinking the phone will think a broken stereo headset was attached or that a single earpiece was attached and still kick over to headphone output.


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Originally Posted by XMetal View Post
The problem I see with this is that your volume through the car would be horrible. All the power that should be delivered to the AUX input would now be dissipated by the resistors and very little power actually gets transmitted to the car's AUX input.
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      08-18-2013, 04:36 AM   #7
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Quote:
Originally Posted by psygnosis View Post
That's really odd, does the AUX disappear from the radio, or does your phone just stop playing?

With my car if I try to charge and listen to my iPhone at the same time it causes a ground loop issue and the radio wont see the AUX input for a moment.
My understanding is there is a resistor doing the same thing for the aux loop so the head unit knows to post "aux" as an input option, but that its only 200mOhm, so not enough to trigger the cell phone to switch over the headphone output.
To answer your q, the cell phone stops playing. There seems to be an auto pause feature upon removal of a headset. This might be disable-able, but I like the feature for when I'm actually using headphones. I think the phone is programmed to update the headphone status between each song, hence without this mod, it senses an open loop and auto pauses.
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      08-19-2013, 08:38 PM   #8
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x3oiler on bimmerfest has a good diagram, and he shows that only a 100k resistor is needed. I have no idea what effect my larger one will have on the performance, but I've gone and asked him. Hopefully he has an answer.

http://www.bimmerfest.com/forums/sho...221&highlight=
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      08-19-2013, 11:37 PM   #9
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Won't make a whole lot of difference. You'll get slightly more drive, so you won't have to turn the phone volume up as high to get it to the same level as the radio.
May also improve phone battery life, but if you have it plugged into the car charger, that won't matter either.
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      08-28-2013, 02:00 PM   #10
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Quote:
Originally Posted by psygnosis View Post
That's really odd, does the AUX disappear from the radio, or does your phone just stop playing?

With my car if I try to charge and listen to my iPhone at the same time it causes a ground loop issue and the radio wont see the AUX input for a moment.
I have the same problem, I've always wondered if it was just my car that did it.

Have you noticed that if you switch back to aux, it will play again, then disappear, then play again, then disappear, increasingly fast? I believe the aux in cable has both a resistor and a capacitor to trigger the head unit to recognize it; my theory is that we are somehow inducing an additional current in the aux cable by charging the phone at the same time, thus charging up the capacitor, which changes the signature the cable gives to the head unit. The increasing frequency with which the head unit drops the connection would seem to support the "capacitor gradually charging up" part.

You can tell I spend too much time thinking about this. It irritates the hell out of me that I have to watch my phone die as I use it for pandora streaming, rather than plug it in at the same time.
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      08-29-2013, 10:22 AM   #11
sipman
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John,
Since I did the cable mod the aux works fine, both on the phone's battery power and when on the charger.
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      08-29-2013, 11:23 AM   #12
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Sipman,

You reported having a problem with the phone; my problem is on the radio side. The phone never stops playing music, the aux input option actually disappears from the radio and the radio switches to FM input instead. I believe we are talking about two separate issues, but i could be wrong.
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      08-29-2013, 12:45 PM   #13
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Nope, you're right. Two different problems. That link I put in a different reply has a good diagram of the aux line from the head to dash input. If that helps, want to document your fix? If you have to get into the dash, it might be the perfect time to wrap those aluminum dash pieces. I seem to recall you had aluminum trim as well. If you do the wrap, I'd love to observe/help.
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      08-29-2013, 01:06 PM   #14
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I have a factory cable from the input to the head unit; I don't think its a problem per se, just an odd behavior. I'll open a poll in the main forum to see if others have seen it.

I do have aluminum trim, but wood is the trim I want; no wrap for that unfortunately. However, I am doing the LCA bushing replacement this weekend if you want to come over and lend a hand.
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