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Help Phone causing speakers of my car to make horrible noises

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dissonantDiva

Lurker
In my car, I like to play music from my phone. I also have a vent clip for my phone, so I can use it as a gps.
However, if my Atrix is anywhere near the front half of my car, my speakers sometimes make this horrible, super-loud, staticky, buzzing, screeching noise. It lasts a couple seconds and fades in and out. It usually happens when I don't have a signal or if my signal is really poor - which sucks because my house is in BFE. So for the first ten minutes of any drive I have to listen to this horrible noise. ><

I *think* it's caused by my phone trying to get a signal, and somehow interfering with my radio? It's very similar to the noise that a computer or tv will occasionally make if your phone is close enough to it, right before you get a call. Except this doesn't happen before I get a phone call.

I tried turning off my wifi, blue tooth, turning the phone on and off, and putting it in airplane mode, but it didn't help. (Well, the noise stopped when the phone was off, but that's counter-productive)

Is there anything I can do, short of ripping my radio out of my car? D:

Thanks in advance. I really appreciate any suggestions!

PS: I experimented a little bit, and an iPhone, a samsung android, and a couple of non-smartphones did NOT make my speakers produce this noise, leading me to believe that the problem lies with my phone.
 
Welcome to the world of a GSM signal.

It's not your phone causing it as much is the Cellular Signal from your phone. When this is happening, it means your data has dropped back to EDGE (2G). This particular band is a magnetic signal... speakers are big electro magnets.... What you are hearing is the electromagnets in the speakers responding to the data pulses.

There really is not much you can do other than keep the phone away from the radio or speakers. Moving the phone higher in the car will improve the wireless signal, and move it away from the speakers. I just keep my phone in a pocket in a pouch I have on my sun visor.
 
WolfmanRobby said:
There really is not much you can do other than keep the phone away from the radio or speakers. Moving the phone higher in the car will improve the wireless signal, and move it away from the speakers. I just keep my phone in a pocket in a pouch I have on my sun visor.
Click to expand...

>_> That definitely won't work for me, I travel often and use my phone as a gps unit and play music off of it. Would a filter, like TgeekB said, help?
 
dissonantDiva said:
>_> That definitely won't work for me, I travel often and use my phone as a gps unit and play music off of it. Would a filter, like TgeekB said, help?
Click to expand...

Most of the filters are "Snake Oil."

Most people sell you a filter that's installed on the power feed to the radio from the car. The problems with that are 1) Stock (OEM) Car radios already have such filters installed. 2) This only isolates the radio from electrical noise generated through the car's electrical system. They do nothing for radio interference.

The problem is that each speaker wire will have to have a ferrite magnet based RFI/EMI Filter installed on the wire. While those are cheap, can you see pulling every speaker out of the car (Door, Dash, Rear deck...) and installing the filters?

To give you an idea what you are looking for, look at the end of a computer monitor cable. You should see a big bulge a few inches from the end that plugs into the computer. That's a RFI/EMI filter.

You can pick them up cheap... less than $2.00 (US) each here Radio Noise Suppression Ferrite Filters
You need one for each speaker, placed on the speaker wire less than 6" from the speaker (So, no you can't just pop them on wire where it comes out of the radio).

Also, if you use a headphone cable to plug the phone into the radio for playing music, you need one there.

After doing all of that, you will reduce it by about 50%.

You can't re-write the laws of physics and that's what you are up against here.... 217-Hz Pulse waveform Radio waves (That's practically in the audio bands) interacting with the speakers. The speaker wires act as powered antennae for amplifying the signal.

Some people CLAIM that they have stopped this by covering the back of their phones in Tin-Foil... Honestly, they must have just peeled a bit off of their HATS to use. Think about it. If you cover the phone to block the radio signals from getting to your speakers, you also block radio signals from getting TO your phone! (IE: Dropped/Missed calls, poor call quality...)

Here's more on the issue...
That Crazy GSM Buzz

If you feel like a full on science lesson... Reducing audio "buzz" in GSM cell phones - 2005-02-03 08:00:00 | EDN
 
Now, there are other options for you, but you won't like #1, and #2 can be expensive, and may not always work.

This only happens when you fall back to EDGE (2G) or GSM bands, meaning you are in a poor coverage area.

Option #1 - put your phone in Airplane mode when you are in bad coverage area's. Thus, you turn off the radio's and there will be no radio signal to pulse. You will have to turn the GPS back on manually, and Google maps won't stream maps (You'll have to use something like N Drive or something that uses locally stored maps cached to your SD card from an OpenStreetMaps server.) You won't get calls or Txt's, but you can enjoy your music in peace.... I told you that you wouldn't like it.

Option #2 - Buy a Radio signal booster for the car. (3Gstore.com, 3G/4G Routers, Antennas, Amplifiers, WiFi, Verizon & Sprint Data Cards - call them and talk to their reps to get the best unit for you.) These can be pricy (A low end will run you $100, a high end will run you $500-$600... You get what you pay for!).
HOWEVER, this may not help in area's that the signal is only 2G, or very, very, very weak. All it will do is boost the 3G when it can detect a 3G/4G. If not, it will boost the 2G signal and make the noise LOUDER.
 
One has to wonder who the idiot of engineer was who designed EDGE. Put any phone near any speaker at BRZZ BRRZZZ BRZZ.
 
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