When watching a channel, MediaPortal correctly shows which channels are available and for which channels no free card is available.

However when selecting a channel from the mini-epg which is unavailable, MediaPortal still tries to tune the channel.

This leads to:
- the wrong channel is marked as active channel.
- its shown in tv OSD.
- so its highlighted in miniEPG.
- its persisted to mp.xml.
- its selected in tvhome => epg shown for that channel.

h4. Steps to Reproduce
- Tune channel x
- Start recording on channel x
- Open Mini-Epg -> unavailable channels should be marked as such
- Click on one of the unavailable channels
- The current channel will continue to play, but the osd information will show the new channel with a message "timeshift couldn't start ... No free card available"


h4. Additional Information
Might be a side effect of http://forum.team-mediaportal.com/mediaportal-releases-315/3667-tvservice-cpu-usage-increases-when-client-playbacks-tv-rec-fullscreen-99197/