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Comment by ChRoss | Hacker News Reader

I have a 3GS, and every time I pick up call from desk phone (with iPhone at the desk), I will experience interference. Now, I need to put my 3GS around half meter away every time there's call to office line. I wonder if anyone experience this also.

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It is the same kind of chatter you might be able to hear in speakers when the phone is nearby? That's a standard GSM thing -- GSM uses specific RF frequencies which induce the noise. ("GSM chatter" is a reasonably common name for this.)

This is one of the reasons I prefer CDMA. It is really, really annoying to be in a public address setting (i.e. a church, auditorium, stadium) and hear peoples' phones in the sound system. Yes, it is a sign of a miswired installation, but in my experience it only happens with GSM phones.

I have a 3GS and I find that I need to place it about a metre from my computer's speakers to avoid audible interference. All my previous phones have done this as well (last before the 3GS was a Sony Ericsson w800i), but they didn't need to be placed as far away from the speakers before the interference could no longer he heard.

Get some speakers that are properly shielded and have ferrite beads on the speaker connection.

My JBL Pro speakers never have interference from my iPhone.

I agree, you must change your lifestyle if you want to use the iPhone.

I have even remodeled my home to include a bedroom dedicated to my iPhone.

Totally worth it.

It's probably time I upgrade my speakers, I've had them for some time now. It's a Klipsch 2.1 set from about 3 years ago. I was under the impression that Klipsch was a reasonably good quality brand, but I guess they're missing these ferrite beads you speak of. Something to keep in mind for when I do upgrade, thanks.

That's interesting. It suggests that your iphone is typically on a 2G GSM network, rather than a 3G UMTS/HSPA network. GSM is known for causing audio interference because the TDMA transmission window cycles at about 200Hz.

Does your 3GS say '3G' on the status bar while it's interfering with your speakers?

In my office room, hardly get the 3G status, but the phone signal is full. I had no problem with my previous phone (Dopod).

Was your Dopod GSM, UMTS, or CDMA? UMTS and CDMA phones won't do generate audio-domain interference. Any 2G GSM phone, from the most expertly-designed Nokia or Ericsson to the worst Huawei will interfere with your speakers.

Usually at home, I see the little wifi symbol as it's hooking on to my router, but if I turn off wifi, your suspicion appears to be correct, I can see that it's on 2G at home. So yeah, that probably has a lot to do with the issue, thanks for the info. My carrier doesn't have the greatest 3G coverage in all areas, but they're currently IMO, the best of a not so great bunch of options in my country.

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