I encountered the same problem with having multiple enclosures hooked up to the nmt. You will most likely get to the screen where it shows the synopsis of the movie but it will not play and go back to the same screen because of the incorrect NMT path.
If you configured your enclosure for example as a device connected to your NMT usb A-1, make sure that it is the first one that you turn ON (or connect first) if you are using multiple enclosures. Otherwise, the NMT will read the enclosure as usb B-1 (if connected or turned on second) and you will not be able to play the file.
I noticed that the usb port assignments on the nmt do not necessarily mean that the bottom or lower part is usb A-1. You can connect a single enclosure to either of the two ports (on m31b) and it will show up as A-1. The second enclosure as B-1...
..hope it helps.
alvinh, your advice is spot on... the eGreat labels my 4 external HDs, from A1 to D1 based on the order that it detects them, ie a first come first serve basis.
To avoid the delay at boot up,
1) i power on the nmt (which has an internal HD), and the yamj jukebox is located in the internal HD...
2) i select Video and it jumps into the index.htm which is for the jukebox covering 4 externals and the internal.
3) Only then, do i switch on the External HDs in order of preference..
why is this quicker?
1) with an external HD attached at boot up, the egreat will auto connect to Drive A1 by default, and this takes a long time... you then need to waste time going to "Media Source" in the menu to go to the Internal HD to find index.htm
2) at that point, the egreat will create indexes for all 4 external HDs and this takes forever.
hope this helps others