Installation of atv flash failing.

I have succesfully jailbroken my ATV and are now trying to install atv flash.

However it says all the time that it can’t connect to my ATV because it appears to be behind a firewall. I tried this both wireless and wired. I tried to reset from iTunes with a new jailbreak. Nothing seems to work.

Any ideas anyone?

One thing that seems to have helped some people is to start playing something via AirPlay and while that is oing on try o install ATV Flash. Why that helps I do not know but it is worth trying.