1. i control MePo with android VoxWav, that worked :-) but i dont want to have for every control a message from the tts. if i ask for artist or similar of course. but if i go left, scroll down or switch TV on, i receive for every step a message. where can i disable this message (which i can not understand)
In VoxWav Pro, there is a toggle button at the top of your screen that says "TTS". If it is on, you can turn it off. But that means you will not get any TTS announcements from VoxWav.
I do not use the MediaPortal configuration so I am not the best person to help you, but I just checked the command presets for that configuration and it is strange that you are getting TTS announcements for all of those minor navigation commands. I see no sign of TTS actions in those particular commands.
Did you install the default MediaPortal configuration that comes with VC?
2. right now i dont know how to set up my own controls. where can i find a tutorial?
As Kalle said above -- see the wiki. There are also links in the wiki to video tutorials, including the introduction to editing commands:
3. how do i set up the TV channels, so i can switch by command "switch channel to ZDF"?
It sounds as though possibly you have not yet scanned your media and generated your XML payloads. I recommend reviewing the installation documentation in the wiki. It is not specific to MediaPortal, but the process is the same.
If you have installed the MP configuration, then you will have two plugins already active in the Plugins menu: MpScan and MpWifi. Take a look at those -- in particular, MpScan. Make sure the MP directories it lists are correct, then have it scan your media.
To see a list of the commands that come preset in your configuration, go to Help > Build Voice Menu. This will open a browser window showing the available commands.
Most of this information is available in the wiki documentation, so if you get stuck start by looking there, then here.
[Edit: see my post below if you have already scanned your media and the TV channels are the only commands not working.]