This report is a follow up of 2887. See attached screendump. Based on the responses in bug 2887, the problem with reading large files seems to be related to smbfs and mmap. As far as I understand, smbfs supports mmap. So, one could expect a mediaplayer to work correctly on a mounted samba-share.
Created attachment 1326 [details] different_data_is_red_back
as already written in #2887 smbfs is really *not* part of Samba, it's unmaintained and broken, try cifs in a recent version instead *** This bug has been marked as a duplicate of 1920 ***