Online Help Center >

Using Audio and Video on

Update to the NPR Media Player and Related Issues

Recently an update was released for the NPR media player. Because of the way certain browsers cache or save files locally, some users did not receive this update and are receiving either an error message 'Undefined -1' or a 'blank' player window. If this is your experience, please clear your browser's local cache and history. After clearing these items, exit the browser window, then re-open a new window before attempting to reload the NPR media player to insure that you receive the latest update.

Common Questions and Issues:


What technology is required to use audio/video on

The NPR Media Player, which is used to play audio and video on, requires the Adobe Flash Player version 8 or later. This player plug-in is available free from Adobe and is pre-installed in many web browsers.

The NPR Media Player is designed for and has been tested with the following platforms and browsers (as of November 2007):

Note that the NPR Media Player is not available for most audio content prior to May 2005. For information about older audio, please see the legacy audio section below.

Are JavaScript and/or Cookies required?

Many features on including the NPR Media Player require JavaScript to be enabled to function properly. also uses browser “cookies” to store information according to our Terms of Use and Privacy Policy. We also use a technology called "Flash Shared Objects" to maintain your playlist for short periods of time for convenience if you close your player window.

How does the "My Playlist" functionality work?

How long do items remain in the playlist?
All items remain in the playlist for up to 7 days after the NPR Media Player was last opened. Opening the player resets this timeout limit. In other words, if you use the player at least once every 7 days, your playlist items should only disappear if you choose to delete them.

How do I delete items? Individual playlist items may be deleted from the playlist by clicking on the [x] at the top right corner of each item.

Example of deleting a playlist item

How do I reorder items? You may reorder items in the playlist by clicking on the vertical grabber area at the extreme left of each playlist item, and dragging the item to a desired location.

Example of reordering a playlist item

What are the specific ports and protocols that the NPR Media Player uses?

The NPR Media Player attempts to connect to our servers over a variety of port/protocol combinations, and uses the first one that works. It first attempts ports 1935, 80 and 443 over the RTMP protocol, and then it attempts ports 80, 1935 and 443 over the RTMPT protocol. Consult your firewall documentation to allow access to these ports and protocols.

At what rates do you stream your audio and video?

The majority of NPR content is streamed at 64 kbps. However, many music concerts, in-studio performances and song selections are streamed in stereo at 128 kbps while video is streamed at 700 kbps to ensure the highest quality playback for our users.

What audio format is the NPR 24-hour Program Stream available in?

The NPR Program Stream is available in four formats: the NPR Media Player, Real Media, Windows Media, and MP3 (for use with WinAmp, iTunes, and other MP3 streaming applications). Visit the Program Stream Schedule for more information.

What are the requirements for audio produced before mid-2005?

Much of our audio produced before mid-2005 is typically only available in Real Media or Windows Media formats. This is indicated by audio links that specifically list Real Media and/or Windows Media options like this:

Example of Real Media and Windows Media Links

If you are having difficulty launching this older audio, please consult our Real Media / Windows Media Help Page.

Video produced prior to November 2007 may be offered in only Real Media format. Again, for assistance, consult our Real Media / Windows Media Help Page.

Does offer audio in MP3 format for download?

Currently, NPR is not able to offer all audio in a downloadable MP3 format due to rights considerations. However, a significant number of NPR offerings are available in MP3 format via our podcasts. In addition, the NPR Program Stream is available in "streaming MP3" format.

Why don’t you support other file formats such as Quicktime or OGG Vorbis?

Currently, the infrastructure and delivery costs associated with maintaining multiple file formats require that we limit the number of file formats that we support.

I get the following error: "The Player requires version 8 or higher of the Adobe Flash Player", but I already have Flash installed. What should I do?

Please consult Adobe’s help pages for troubleshooting Flash installations for Windows, Intel-based Macs or Linux or Solaris.

I select an audio link and nothing happens, or I hear a "click." What should I do?

When you select an audio link, attempts to open a new browser window that contains the NPR Media Player. If you hear a "click" or "pop" or see a message at the top of your browser window when you attempt to launch audio/video, please set your pop-up blocker to allow to launch windows.

A player window opens, but the audio doesn’t start. What should I do?

You may need to change your firewall settings to permit the NPR Media Player to stream by allowing access to the proper ports and protocols. (Please consult your network administrator or service provider). This may be the case, even if you are able to use audio or video on other sites, because different sites may deliver their media using different streaming methods.

When I click "Add to Playlist" or "Listen", the item isn’t added to my playlist. How can I fix this?

If you have installed the FlashBlock plugin for Firefox or other browsers, you may experience problems adding items to your playlist. To remedy this, you will need to add to the "whitelist" list of the FlashBlock plugin.

My player keeps "buffering". What should I do?

There are known issues with player performance on low speed connections, particularly dial-up.

If you are on a high speed connection, and your player has recently stopped working and displays a "buffering" message, please clear your cookies for There is a temporary problem with cookies that impacts the player we are currently working on. If clearing your NPR cookies does not resolve the issue, please fill out a Support Request.

Here are several other options we can recommend for listening to NPR audio:

  1. The NPR 24-hour Program Stream continues to be available in multiple formats including Windows Media, Real Media, and Streaming MP3 (for WinAmp, iTunes, and other MP3-capable players). These streams can be accessed on our program schedule page or via the “schedule” link near the top of the home page.
  2. Another option is to access our text-only site, which is available at This site, originally designed for screen readers and mobile devices, provides streaming audio in a low-bandwidth Windows Media format. The text-only site offers access to recent programs and recent content by topic area.
  3. Many NPR member stations provide audio on their individual web sites. This audio is typically available in a variety of formats, including Windows Media and Real Media.
  4. Additionally, many NPR programs are available for download via the NPR Podcast Directory -- Podcasts are MP3 files that can be downloaded to your computer and played locally, avoiding the unreliability of network connections. Many podcasting applications, such as the popular iTunes software, can be configured to automatically subscribe to particular content and download it automatically so that it is available to you when you want to listen.

How do I clear my cookies?

NOTE: on Firefox and Safari, you can search for and delete ONLY your cookies, but on Internet Explorer, you will delete ALL your cookies.


  1. In your browser's menu bar, click on "Tools"
  2. Click "Options..."
  3. Click on the "Privacy" tab
  4. Click on "Show Cookies..."
  5. Find all the cookies for, select them and click "Remove Cookie"
  6. Click "Close" to exit

Internet Explorer

  1. In your browser's menu bar, click on "Tools"
  2. Click "Internet Options..."
  3. Under "Temporary Internet Files" on the General Tab, click "Delete Cookies"
  4. Click "Ok" on the dialog box that says, "Delete all cookies in the Temporary Internet Files Folder?"
  5. Click "OK" to exit


  1. In the OSX menu bar, select "Safari"
  2. Click "Preferences..."
  3. On the "Security" tab, click "Show Cookies"
  4. Click on "Show Cookies..."
  5. Find all the cookies for, select them and click "Remove"
  6. Click "Done"
  7. Close the Preferences box.

How do I clear my local browser cache and history?

Note: It is important to exit and close all browser windows after clearing your local cache and history before attempting to re-open the NPR media player

Internet Explorer Windows

  1. In your browser's menu bar go to Tools --> Internet Options --> General --> Browsing History --> Delete...
  2. From this window delete the Temporary Internet Files, Cookies and History.
  3. Close this window, then select OK before exiting the browser.

Firefox Windows

  1. In your browser's menu bar, go to Tools --> Options --> Privacy
  2. From the Privacy window select the Settings... tab found in the Private Data subsection
  3. In the Private Data subsection window choose Download History and Cache and select OK.
  4. To clear NPR only cookies, go to Tools --> Options --> Privacy
  5. Select Close and then OK again before closing the window and exiting the browser.

Firefox Mac OSX

  1. In the Mac OSX menu bar, go to Firefox --> Preferences --> Privacy
  2. From the Private Data subsection select the Settings... tab and choose Cache, Browsing History and Download History only and select OK
  3. Close the Preferences window and Exit the browser

Safari Mac OSX

  1. In the Mac OSX menu bar, go to Safari --> Empty Cache

I’m having problems playing older (pre 2001) audio in RealPlayer. What should I do?

Version 11 of RealPlayer does not currently support certain types of Real Audio files found on NPR from the year 2000 and earlier. If you have recently upgraded your RealPlayer to version 11 and are experiencing difficulty listening to Real Audio from this time, you will need to uninstall RealPlayer 11 and install RealPlayer version 10.5, which can be found on Real's site. (Locate your operating system and look for the RealPlayer 10.5 link.) More recent Real Audio formats found on should continue to work with RealPlayer version 11.

Still having trouble? Fill out a Technical Support Request form.

If you fill out our Support Request form this will provide information to NPR and we will do our best to assist you in resolving media player issues on supported configurations as described above.

NPR thanks our sponsors

Become an NPR sponsor


Browse Topics



PBS logo