Issue with my regex

Question

I try to parse a small part of a webpage. As I need to analyse a part of executed JS I can't use a HTML parser. Well, as what I have to find is "easy" I used preg_match().

When I validate my code in regex101.com everything seems to be ok and I get what I want. But when I execute my code it does not work correctly.

Example of what I try to parse:

// Setup SoundManager
soundManager.setup({
    debugMode: false, 
    flashLoadTimeout: 1000,
    flashVersion: 9,
    preferFlash: true,
    url: "path/swf/",
    useHighPerformance: true,
    useHTML5Audio: false,
    waitForWindowLoad: false,
    onready: function() {
        soundManager.createSound({
            id: "radio",
            serverURL: "rtmp://popradio.stweb.tv:1935/popradio/",
            url: [{
                type: "audio/mp4",
            }],
            autoLoad: true,
            autoPlay: true, 
            multiShot: false,
            volume: volume,
            onconnect: function( bConnect ) {
                setButtonStop();
            },
            onfailure: function() {
                setButtonError();
            },
            onload: function(bSuccess) {
                if (bSuccess == true) {
                    setButtonStop();
                } else {
                    if (window.onloadRetry != 2) {
                        window.onloadRetry++;
                        soundManager.reboot();
                    } else {
                        setButtonError();
                    }
                }
            },
            onplay: function() {
                setButtonStop();
            }
        });
    },
    ontimeout: function() {
        setButtonError();
    }
});

I just want the value of serverURL so I made :

if (preg_match('#serverURL: "(.*)",#', $html, $rtmp)) {
    $streamurl =  $rtmp[1] ; ;
    echo $streamurl ;
}

But it never ends, it mades me a display of the whole webpage (from ServerUrl: )

What did I make wrong? I read the docs about preg_match(), but I did not find anything.