This is happening because you have the QuickTime player installed and it is set to play any online media file in your browser. There are two ways to fix this, one if you’re using Internet Explorer or Opera and another if you’re using Firefox.

Internet Explorer/Opera

1. Open Quicktime Player
2. Go to the Edit menu, go down to Preference, then click on QuickTime Preferences
3. Click on the Browser Tab, then click on MIME Settings…
4. Expand the area labelled MPEG – MPEG System, video, and audio files
5. Uncheck MPEG Audio
6. Press OK
7. Finally, press Apply

Firefox

1. In Firefox click Tools > Options…
2. Go to the Downloads tab
3. Near the bottom under Download Actions, click View & Edit Actions…
4. Select the MP3 Extionsion then click Change Action… at the bottom
5. Once here, just select the radio button that says “Save them on my computer”
6. Click OK and Close out of options

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