Soooo slow and does not connect to larger directories

[AndroidInKigali]

I want to connect my Samsung Galaxy S3 GT-I9300 Android 4.1.1 with AndSMBPro 2.0 (System info: 3.0.31-256827 Dalvik 0.9) to my Windows Server 2008 R2 SP1 shares using my domain credentials.

Symptoms: After it takes more than 70 s to login to the server (CONNECT smb://x.x.x.x:445 and DOMAIN ... USER ... PASS) the server's shares and printers are displayed (LS /). After selecting a server share, the CD command takes another 90 s to complete. After another 60 s (LS command) the new directory (the share's root directory) is displayed. Selecting a subdirectory with 155 file entries does NOT SHOW the directory list (LS command) even after 5 mins

I already upgraded to the Pro version, but this behavior did not change/improve.

Anything that I can do to make it work?

Ralf