iPhone: Vibrates randomly

I have this and more.

My phone was replaced earlier this week, the replacement was bad so this is my 3rd phone this week.
The phone buzzes/vibrates randomly.
The phone freezes.
The phone gets the start-up wheel randomly.
I've done all the re-starts, shutdowns and more.

All this is particularly prevalent when the phone is plugged into the computer to recharge.
Then it seems to shut down some computer functionality as well.

It's making me crazy and wishing I had my old phone back which had to be replaced because it gave me a constant electrical charge when it was plugged in to charge.

ARRRGGGGHHH!!!

my iphone has just started to do this, every now and again it vibrates, nothing comes up on the screen though, so i dont know if im just not getting messages or something? getting really annoying turned it on and off numerous times still no change
any help would be sickkkk

Problem 1
I am currently having the same problems. I have an iPhone 3G and am finding that it just randomly vibrates, for no reason. When this happens the icon shows up that it has been changed to silent. This can happen at any time, even when it is just sitting on the bench.

Problem 2
While using the iphone ipod it just randomly turns the volume down to silent, it was at about 70% volume. Once it is silent it is very hard to turn the volume back up, you cant use the side buttons you have to use the scroll bar within the ipod.

Things tried to fix problem: I have turned it on and off, then reset it and restored it. I was wondering if there are any trick to fix this annoying problems that I have.

This happened to the 3GS that I purchased recently. For me, it is because I have the Facebook App and the phone vibrates when someone tries to chat with me. I couldn't figure it out for the longest time as I was not getting emails or texts to cause the vibration. If you have Facebook or other social networking apps, check to see if you've received a message / chat request / etc. next time the random vibration occurs.

I had the same problem on my old 1st Gen iPhone... Started after the 3.1 update, I believe.

In particular, it would vibrate for no apparent reason after I had hooked it to the charger and then put the phone to sleep. I'd get a series of vibrations. One time it would vibrate on/off every second, and didn't stop until I did a reset on it.

For what it's worth, the problem seemed to resolve itself... That or I don't know what I did to fix it...

I now have a iPhone 3Gs, and have not experienced the random vibrate on it...

Sorry I don't have a fix...

Bob

I'm having the same problems exactly.

I've got an iPhone 3G 8GB.

You may have your email set up to automatically fetch new mail?

Mine does this every 30 mins and the phone vibrates and if you look at it without unlocking it seems like nothing is there..

Hope this is the answer you need....

Garvan