only call IPlayerCallback::OnPlayBackSpeedChanged if the speed has actually changed

[vuplus_xbmc] / addons / skin.touched / 4x3Hirez / Startup.xml

<window>
        <defaultcontrol always="true">10</defaultcontrol>
        <allowoverlay>no</allowoverlay>
        <controls>
                <include>CommonBackground</include>
                <include>CommonNowPlaying</include>
                <control type="button" id="10">
                        <description>trigger</description>
                        <onfocus>ReplaceWindow(Home)</onfocus>
                        <texturenofocus>-</texturenofocus>
                        <texturefocus>-</texturefocus>
                </control>
        </controls>
</window>