i recently purchased a 27″ iMac, when i connected it to my Drobo FS via Samba the videos where slow and there was an interruption every few seconds when playing movies via VLC which wasn’t the case with Win7,
initially i thought it was a VLC problem and tried different solutions and none worked.
i stumbled across some posts on the web having similar problems of slowness on Snow leopard and the solution was to change the TCP ACK Delay parameter :
sudo sysctl -w net.inet.tcp.delayed_ack=0
in addition to adding the ip of my Drobo to /etc/hosts this helped speedup the finder browsing my folders.
to make the settings permanent:
sudo vi /etc/sysctl.conf this will edit the file or create it if it doesn't exist
add the following line:
i tested the videos later and the played perfect, it also worked with Air Video and improved the performance alot
i love my Mac