2.3 gingerbread - Every time I plug in my phone via USB it automatically mounts the SD card (Xperia Arc version)

I have almost this question:

Every time I plug in my phone via USB it automatically mounts the SD card

I have a Motorla Droid running CM6 (essentially Android 2.2). I'm connecting to Windows 7 machines via USB. Every time I plug in my phone via USB it automatically mounts the SD card as external storage.

Except I have a Xperia Arc with version 2.3.4, and have neither Winamp or DoubleTwist installed (given as culprits in the other question).

This behaviour started when I updated to 2.3.4 (I don't know exactly what version I had before).

How can I stop it?

Edit: I've no "Connect to PC" section in the settings, nor can I find this setting in other sections such as "Storage"

Answer

Go to Settings->Sony Ericsson->Connectivity and un-check Auto connect in MSC.