Hey Daniel,
first of all, thnx for the quick reply. For the cookie thing: In order to clean my registry, I already deleted all cookies and stuff. I also tried to use another browser (IE nstead of Firefox). Same problem. The only place i can post anything is the "General Chat".
Now back to topic: Problem solved!!!

and damn happy about it.
I just wonder...well...wait...
My mistake was, to use output 3/4 instead of 1/2. Putting the chinch cables in 3/4 caused the issues I posted above.
I just wonder problems like that don't appear in the FAQ or troubleshooting (neither the .pdf nor the paper one). Same is for "Error Code 88780064" wich you get whenever you try to use Winamp, Win Media Player or whatever without switching from the Asio Soundcard to the mainboard one. The problem is simple, and it's obvious, that someone with no experience in setting up audio hardware, drivers n stuff will stumble across problems like that.
The forum has a few post related to that error code 88780064 thing: "can't record anything at all" and so on. Some members posted soluions like "use audaciy" or "use the microphone input of your onbord soundcard to record sound" wich is defniately errr...the stuff that bulls drop when full. The correct answer would have been and would be: switch from the ASIO card to your onboard / regular soundcard.
Well...I am very happy that everything works fine for me now. Finally I'd like to leave some minor suggestions to anyone who's responsible:
1.The provided soft- and hardware can be used in 6 or more languages, but there's only a french (je ne sais pas pourqouis) and an english documentation. Hireing people to translate the documentation would probably cost 100 to 150 bucks each langauge. Why not hire them and make the product cost 10 bucks more?
2.Add the Error Code 88780064 and the mixed function problem to the FAQ.
3.The process of registration and whats related to it is a bit confusing, since the engleeshe is obvoiusly written by a non native english person. Hire another person to fix that. Put another 2 bucks on the products price.
4.Hire an experienced webmaster, to fix the Forum.2 more bucks on the product.
5.Keep up the good work.
Don't get me wrong. I am very very happy about U-Mix Control Pro 2 and stuff. It's really a great solution for digital DJing. I'm just trying to suggest things to make things a lot easier.
Thanks, Good Luck and good night!
