Films not showing on dlna players

osx 10.8

Hi, I have just transferred to mac and when I transfer new video mp4 files to WD mybook live they do not show on any dlna player and I have 3.  They do show on wd2go on my iPhone but not on my normal ace player iphone app or tv’s.  I have tried rescanning the mybook live and rebooting but not working…was all ok pc

UPDATE: When I go thru mac finder and change the file name it magically appears? Any idea if I am doing something wrong?