Don't no if this will help but I will throw it in to the pot anyway. I was having real problems last week with getting streaming to work on my desire via Wifi (router is Dratek 2600). Eventually tried the nuclear option from a security point of view which was to set up my phone in a DMZ. Since then have had no problems with wifi or streaming.
Send my regards to Denmark by the way, I used to live in Ballerup outside Kobenhavn.
What do you mean by setting up your phone in a DMZ? And I'll say hi next time I'm in Ballerup
I don't get out there much though... Especially now when it's too hot to move.