I notice a lack on consistency in the posts regarding duplication of controls.

On the one hand some people are saying that duplication of controls is a bad thing (For example, with regard to the wheel and the stick doing FF/REW)

On the other hand some people are suggesting that duplication of controls would be a good thing (For example, having both the wheel and the buttons do volume)

I don't think it's possible to generalise when it comes to duplication of controls - You have to look at the control context of every situation differently.

However, if I were forced to generalise I would say that in a situation where the user might want to achieve fewer different operations than there were buttons available to achieve these, then duplication of controls is a good thing if it offers the user a different type of control to achieve the same function.

For example, in the main player screen on Karma, both the stick and the wheel perform seeking - This is a good thing since the user has a choice of seeking mechanisms, seeking with the wheel is a very different experience to seeking with the stick.

The same can be said for the menu system - There are only four operations that the user could possible achieve in the context of the menu system: Up, Down, Select, Cancel/Back. There are more than four controls on the player, and since one of them is a wheel not a button it makes sense to duplicate the up and down button controls to allow for faster navigation through the menu or list.

Further to this, not duplicating controls in some contexts could be potentially concerning for a user. Using the menu system argument again, if we decided not to duplicate any controls then we would only have the stick. The fact that the menu button and the wheel don't do anything would, in my opinion, be more annoying for the user than the fact that they do the same thing as the stick.

There are two counter arguments that need to be finely balanced in order for the resulting product to feel intuitive to use: The duplication of controls, and the overloading of controls.

My feeling on the volume/knob issue is that it would be nice to be able to change the volume with the knob, as Rob suggests this should be a user configurable thing. However, I don't favour the dialog box approach to configuring the wheel for Karma. I think that the wheel should be configurable by pressing and holding the wheel which brings up a widget with which you select the wheel function (seek, volume, etc) you click the wheel when you have chosen the desired function. This way we can assign any number of future enhancements to the wheel (for example cross fade period could be set in this way, or shuffle setting chosen, or even pitch control of the audio) and the user gets the ultimate choice of what they want their wheel to do.

Toby.