/*
* Set the stereo volume level.
*
* This method raises an Xmms::Error exception if XMMS is not running.
*
* Examples:
* remote.set_stereo_volume left, right
*
* stereo_volume = [10, 0]
* remote.set_stereo_volume *stereo_volume
*
*/
static VALUE xr_set_stereo_vol(VALUE self, VALUE l, VALUE r) {