Speakerphone suddenly always "on" WTF?

[PKSlice]

I have had the Galaxy SII for six months and it has been great, but suddenly the speakerphone is now always "on" by default for incoming calls. I can turn it off every time a call comes in because the speakerphone icon appears during the call, but how do I disable it? It's very annoying.

Nothing in the manual about this.

???

[stonkr]

In no particular order, have a look at...

Driving mode, is it on, what settings is it using.
An app that might use driving mode. Did you recently install a nav app or similar, was it setup properly, does uninstalling it clear the problem.
Vlingo (double press home button), is it setup, is driving mode activated, try activating then deactivating the various settings etc.

If those don't solve it we'll see what else might be the cause.

EDIT: Have you turned your phone off recently? Always a good idea to restart every day if you don't turn it off at night to charge.