Source Browser ?

1\definerenderingwindow
2  [example]
3  [width=0pt,height=0pt,frame=off]
4
5\setupinteraction[state=start]
6
7\useexternalrendering
8  [mysound]
9  [audio/mpeg] % audio/x-mp3
10  [akkerman.mp3]
11  []
12
13\definereference [StartSoundTrack] [StartRendering{mysound}]
14\definereference [StopSoundTrack]  [StopRendering{mysound}]
15
16\definelayer[resources][width=\paperwidth,height=\paperheight]
17
18\setupbackgrounds[page][background=resources]
19
20\starttext
21
22    \setlayer[resources]{\placerenderingwindow[example][mysound]} % once
23
24    \startTEXpage
25        \button{start}[StartSoundTrack]
26        \button{stop}[StopSoundTrack]
27    \stopTEXpage
28
29    \startTEXpage
30        \button{start}[StartSoundTrack]
31        \button{stop}[StopSoundTrack]
32    \stopTEXpage
33
34\stoptext
35