Frustration time

Nothing to do with the Nieuport, I hasten to say!  I've been having a battle with the sound system at the Aviation Heritage Centre, trying to add some more "fly by" aircraft sounds to the card.  So no pictures for this particular post. The first problem is that there is very little documentation about the system -and what there is, is in 'tech-speak', which means lots of "trials and errors" (mostly the latter).  The first error was discovering (belatedly) that it only likes mp3 format so my attempts at producing 4 minutes of silence between sounds didn't work - they ran together.  Having fixed that by finding some freeware to convert wma to mp3 format (how do you make sure that you don't land up getting something insidious that's liable to take over your PC?), the player decided to cut short the 4 minutes into 15 seconds. How it could do that I have NO idea.  So I mess around with the naming of the various tracks (consecutive numbering, putting them in alphabetic order) only to find that, hooray! my 4 minutes silence works -but that it is only playing the first two fly-by sounds rather than the 4 I'd put on the card.  I thought these players just played what was on the disc rather than trying to decide by itself what it is that I want it to do.  The trials and tribulations will continue....