Prefix of tmp instead of file; Slim::Player::Playlist::url

Hi guys

Bit of an odd issue I noticed today. I recently upgraded to LMS: 7.9.0 - 1440747495 @ Sat Aug 29 04:05:24 CUT 2015 at the weekend.

I kicked off a SugarCube/MusicIP mix on my Radio;

Radio
Player Model: Squeezebox Radio
Player Type: baby
Firmware: 7.7.3-r16676
Wireless Signal Strength: 93%

and noticed that no tracks were queuing up as I was getting strange results from the following function;

my $song = Slim::Player::Playlist::url($client);
$log->debug("URL Reported;$song\n");

It was returning tracks like this (NOTE the tmp);
URL Reported;tmp:////FATCAT/music/music/Massive%20Attack/Heligoland/etc

Yet moments ago when I was listening on my duet I was getting the normal;
URL Reported;file:////FATCAT/music/music/Thievery%20Corporation/etc.

The switch of tmp instead of file, broke my code. :(

I've not seen the tmp before, yet each track I selected from the Radio returned the same tmp prefix. (All tracks are on a NAS system.)

I can add a code fix into my code but wondered where the tmp came from, is there a change I need to cover off? Strangely enough, without any code changes I just selected a track from the LMS Web GUI and everything worked fine again.

Any thoughts

Cheers