All/Zaerc do you remember that I was having issues similar to yours over SMBFS vs CIFS some time ago. You had provided a patch that meant in the end I just had to config smbfs instead of cifs in the admin site and it fixed it (took a long time to get to that point) - but before that my windows shares just wouldn't stay online as far as the core was concerned even though they were actually online.
Happened with every install completely repeatably - the share was discovered and media added, then immediately failed and never came back.
dmesg reports smb_add_request timed out and smb_proc_readx_data errors - the only references I can google date back to 2005 and an earlier kernel, but clearly talk about freezes with smbfs shares as well, and that cifs was a workaround!
Perversely - I tried switching to cifs again.... now the share seems to be online!!! How frustrating and inexplicable! But those messages have gone away, and so far (after 15mins) a media file has not yet hung on me....
This seemed to be effecting DVDs as well, presumably because it is a complete hang, but have also had DVD bomb out with CSS lib issues fully 20 mins into the show!
Problem is, as happy as I would be to be back with the default cifs, I am effectively stuck between a rock and a hard place, reliability-wise. Using cifs and I risk the device-offline issue coming back randomly at any point, staying with smbfs, suddenly I have periodic freezes of the system.
(btw, this seems unrelated to the sound in VDR/KDE issue that I am also having and the subject of another thread)