If you use extensions (Firefox/Tools > Add-ons > Extensions) that can block content (e.g. Adblock Plus, NoScript, Flash Block, Ghostery) then make sure that such extensions aren't blocking content.

Start Firefox in Safe Mode to check if one of the extensions (Firefox/Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Firefox/Tools > Add-ons > Appearance).

• Do NOT click the Reset button on the Safe Mode start window.

• https://support.mozilla.org/kb/Safe+Mode
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

I disabled AdBlock and did the Safe Mode drill. (DEFAULT theme was already selected.) Thank you but no joy. In FireFox options>applications is there an 'idea' application for playing MP3s? (Amazon.com MP3s play automatically without selecting an application to play the MP3.)

You can set the Boolean pref media.windows-media-foundation.enabled to false on the about:config page to disable the built-in HTML5 media player.

• http://kb.mozillazine.org/about:config

I cannot access <about:config> from FF address bar. Where else may I access <about:config>?

I found <about:config> and changed to <false>. No joy. Changed back to <true>.

Try to disable all unneeded plugins to see if that helps (I see an Amazon MP3 Downloader Plugin 1.0.17).

• https://support.mozilla.org/kb/Troubleshooting+plugins

I disabled all of my plug-ins and the Amazon sampler still doesn't work. Still no joy. (If I want to 'sample' I open the page in IE and it works fine.)

What would happen if I deleted FF and reinstalled it? Would I loose bookmarks, etc.?)

Clear the cache and the cookies from websites that cause problems.

"Clear the Cache":

• Firefox/Tools > Options > Advanced > Network > Cached Web Content: "Clear Now"

"Remove Cookies" from sites causing problems:

• Firefox/Tools > Options > Privacy > Cookies: "Show Cookies"

No joy. Thank you cor-el. I called Amazon.com MP3 help and they are forwarding the problem to their tech people. Not sure how they can suggest a fix for a FF issue but I appreciate their help. Would be nice if Mozilla had a call in feature so that someone could actually talk to a tech-type. I do have a work-around in that I can open the FF page in IE and play MP3 without any problem. But I don't like work-arounds. I like software that works the way that it was intended to work. Thanks again cor-el. If something else comes to mind let me know. Dave71

I have exactly the same problem, using Firefox 23.0 with Windows 7. Have never had this problem before with Firefox and Amazon, and the mp3 samples still play with IE, which I prefer not to use. I have tried numerous mp3 samples (many of which I have previously listened to before downloading) and now get one of two messages: "error 3" or "unavailable." I have called Amazon support and the person with whom I spoke was not able to figure out the problem but escalated it to a higher tech level. I am waiting to hear if they can resolve it.

It's like looking into a mirror. Same set up and same experiences. I don't see that either FF or Amazon are doing squat. I can do a 'work around' which is simple enough using IE (which I too detest) conversion of the FF page. But being who I am I like software to do what it is intended to do. I also like IT people to resolve problems (hint! hint!) rather than devise new gimmicky do-dads that 95% of us could care less about (unless they improve security without unduly encumbering the user).

I was having the same issue. I use the "https everywhere" add on. Disabling it for the Amazon sites fixed this issue for me.

BEAUTIFUL! You solved the problem! Thank you! Why 'the pros' didn't solve this problem immediately is ... interesting.