CDJ2000-NXS emergency loop, now loading, and DELETES PLAYLISTS

Hi. Firstly, I've tried searching the forums for this, but can't find the info I'm looking for. If I've missed something, please link the appropriate thread.

I look after the DJ gear, audio and lights for a high profile nightclub. A few DJs have had issues with the DJ equipment in our main room these last few weeks.

Our setup is 4x CDJ2000 nxs (v1.21), a DJM900 nxs (v1.31), all linked via standard Cat5E cables (2m) and an Asus 10/100 network switch (8port). Our DJs use assorted USB flash drives, presumably with assorted versions of recordbox. Being both local and touring acts, it's impossible to keep up with who is using what versions etc.

Recently, DJs have experienced players going into emergency loop, both playing from local media, and via link. On one particular instance, the local player was in emergency loop, and the other 3 players displayed loading, with the circle graphic going around. This only lasted about 15 seconds, then the player continued playing happily and the other 3 also returned to normal. Other times we haven't been so lucky, and have been stuck in an emergency loop that isn't quite in beat. This has happened with assorted tracks from assorted USBs, but doesn't repeat when the same tracks are played, and then a known "good" track will have the same problem. Sometimes it happens several times in an hour long set, and other times (today, for example) using the same USB I can play 2 hours with no issues.

In an effort to diagnose the problem, I have tried swapping network cables, the network switch, and also swapped what we thought was the faulty player for a spare 2000nxs player from the store room. None of these actions seemed to make any difference. It is worth noting, that the spare player is on newer firmware, v1.22. Again, this didn't change anything, however this newer fw player had the player number illuminated, and the utility menu said it was connected, when there was in fact no cat5 cable connected to this unit.

To avoid more problems, midway through Saturday night, all cat5 links were disconnected, and DJS instructed to only use USBs directly inserted into each player, after which there were no further problems. Until, however, a DJ only had one USB with him, and was forced to use LINK. Upon connecting the links, the currently playing unit went to emergency loop, and also deleted playlist data from his USB drive. He continued playing, borrowing a USB from another DJ, and luckily the songs from the playlist were still on the USB, however they were no longer in a playlist.

I'm really quite stuck on this one, any help would be greatly appreciated. We finally managed to convince DJs that the nexus decks were ok, after earlier firmware updates resolved other problems several months ago, I'd hate them (and me) to lose faith in them once again.

Cooper