"Device not supported" message keeps popping up..

[Khurram]

Since yesterday I keep getting the device not supported message randomly popping up on my iphone 4. There is no accessory plugged in and I keep losing the phone sounds as well (unlock screen, on/off etc.) It's started to happen more and more often. I've tried cleaning the connector area by using duster spray but it hasn't fixed it.

I also did a restore and it's still there.
Any fixes or do I need to take it in?

 

[Roessnakhan]

Check the water sensor if you haven't already - that happened to my 3GS and I found out the water sensor had been tripped.

 

[-aggie-]

Definitely a sign of water damage in the dock connector or maybe dust and dirt, if you're lucky. Check the sensor, and if okay, use a small paint brush to clean the area.