Can't get .m3u video playlists to work

I am trying to get a video playlist to work - the filename is playlist.m3u in the same directory of the USB device as the files it is trying to play.  When I select “Playlists” on WD TV, it shows a folder called “playlist.m3u”.  If I press play I get the red “not permitted” circle.  If I press enter, WD TV says the folder is empty.

The playlist is as follows:

#EXTM3U

#EXTINF:179,1. Hero Takes A Fall

01 — Hero Takes A Fall.mp4

#EXTINF:223,2. Going Down To Liverpool

02%20%E2%80%94%20Going%20Down%20To%20Liverpool.mp4

#EXTINF:190,3. Manic Monday

03%20%E2%80%94%20Manic%20Monday.mp4

#EXTINF:231,4. If She Knew What She Wants

04%20%E2%80%94%20If%20She%20Knew%20What%20She%20Wants.mp4

#EXTM3U

#EXTINF:179,Clip1

Clip1.mp4

#EXTINF:223,Clip2

Clip2.mp4

…etc.

What is going wrong?

Thanks.

BJ.