How do I turn off the Ipod Charging Tone?

Question

Firstly please don't say by turning down the sound slider because if I do I can't play the music on my ipod whilst it's charging.
Right the situation is that my iPod touch is connected via usb in my car so I can play music on the move, also as a bonus my iPod is charging at the same time, but here's the problem because it is charging not only do I get the music from the iPod I also get the annoying charging tone through the speakers. I can't find a setting for this specific tone in the settings, and searches would suggest that it can't be turned off. I do hope this is not the case becasue if it is it's madness. Also if I connect via aux cable if the usb is connecting ie the iPod is charging I still get the charging tone trilling it's merry way.
How can I turn off this tone. I know I can disconnect the usb ie stop the charging but that defeats to object as I then gradually use up the power meaning on long journeys I have to either dispense with the iPod or put up with the tone. Also when I get to my destination instead of having a fully charged iPod I am already down on power.
HELP?

Answer 1

Okay, well I'm still not aware of any iPod which repeats the charging tone. Have you checked in the Connector recess of your iPod to make sure there is no muck in there, or that there is no damage to the connector pins? This is because I still think that the connection between the cable, dock or whatever and the iPod is not staying "made". In other words, the connection is disconnecting and reconnecting and every time it reconnects, the beep sounds.
Can you watch the iPod's display? When charging, the battery symbol shows the lightning bolt or, when full, the plug in the battery. Does that change to the battery only just before the charging beep? If so, that suggests that the connection is being repeatedly broken and re-made. Also check the cable (just in case).
If you cannot solve this I think there are two options available to you.
Ask any of your friends (who have an iPod Touch with the same iOS version on it) if their iPod does the same as yours; if they are aware of a setting for this and if so, how to turn it off, or; 
Make an appointment at the Genius bar of your local Apple store and see if they can sort this out.
Like you, I do not see the "change with buttons" option mentioned by kartabyaa, although I only have iOS 4.2.1 on my Touch. (I don't believe the iOS version is different to mine in this respect, but if you ask someone with the same iOS version as you, that should help confirm or refute what the iPod can and should do.)
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