sp 2 and file access time delay

[julio]

I have an application developed in .net, that is essentially an audio
player, it can perform searches on a db on a server, and then play audio
tracks (the audio tracks too are on a server, another machine on the
intranet)

this system has always worked great, and accessing mp3 files on the
server is immediate on the 100 Mb intranet.

I have noticed that installing sp2 a BIG delay is introduced while
opening audio files to play, it is 1 second long or more and makes my
application unusable.

the problem has nothing to do with firewall ( I've disabled it on both
client and server machines ), and more a strange thing is that the
problem shows up if sp 2 is installed on the CLIENT machine ( the player
who asks for audio files ), and makes no difference if the server ( the
machine serving the audio files ) has sp2 or not.

somebody is experiencing the same problem?

any thoughs?

thank you,

Giulio