Acast provides lots of different options for sharing your podcast, including feed distribution to third-party platforms and the Acast embed player. In case you want to use episode audio files hosted with Acast directly on your own website or player, we have some best practice guidelines on how to do this — and to help you ensure your listening data remains accurate.
This article talks about two types of implementation: auto-play and pre-load.
Auto-play triggers audio to play without the user needing to press anything, such as when the website first loads.
Pre-load is used to improve the responsiveness of a site. In this case, the audio will not play automatically, but the file will be downloaded when the page is loaded. That means, if the listener then chooses to play the episode, it will already be ready for them.
Both methods have their downsides and violate Acast Community Guidelines and well as IAB guidelines, which is why we are against the use of either implementation. Auto-playing can be seen as a bad experience for listeners, while pre-loading will inflate your show’s download statistics behind the scenes — which will affect the accuracy of your listening data.
IAB Guidelines - Summary
Below is a summary of all the player recommendations to publishers using their own players, provided by the Interactive Advertising Bureau (IAB). It's important to follow these recommendations to ensure you have accurate listening data:
Do not implement Auto-play. This will result in a bad user experience for the user with audio they were not expecting to hear.
Do not Pre-load - unless the intent was clearly to play the podcast.
Use header information - located at the start of the podcast to prevent a full download when not needed.
File request - For a full download, ask for the entire file in one go. For a progressive download, ask for the file in slices (byte range). This way a full download can be distinguished from a progressive download.
Do not modify the enclosure URL when requesting media - don’t add extra parameters.
Do not cache podcast episodes on your servers. Always download the latest episode from the enclosure URL for every app user wanting to listen.
Use the GUID - as opposed to episode URL, title, publication date, etc - to identify new episodes in the RSS feed that should be automatically downloaded to a user’s device. The GUID is designed to be persistent through changes to host platform, title changes, etc.
Employ an “automatic download unsubscribe” behaviour if your player allows listeners to enable automatic downloads (e.g. - stop auto downloads after 5 episodes of non-listens).
Do not automatically download all episodes (e.g. back catalogue episodes) by default. This creates unnecessary drain on the publishers’ servers and consumes users’ bandwidth.
Why does pre-loading an episode file affect podcast statistics?
In the podcasting industry, we measure statistics by filtering download requests made to our servers for the episode files. We are certified as IAB 2.1 compliant, which means we adhere to the industry standard guidelines of how to filter podcasting data received. You can read more about the details here.
In more technical detail, along with other filters, if our servers receive a 200 GET request for a full file download or a 206 GET request for more than a minute of audio, we will register that as a listen in our analytics dashboard. This means that your site’s pre-load request is being registered as a download — even if the user never actually chooses to listen.
The IAB also provides guidelines for podcast players in its full documentation. 'Appendix 7 - Podcast Player Recommendations’ is the section of the guidelines specifically about services that play podcast episodes. It states that allowing pre-loading or auto-play of episodes on your website, where the intent of the listener to download and listen to the podcast is not clear, will result in inflated statistics for your podcasts.
Therefore, In line with the IAB recommendations, you should explicitly prevent pre-loading of podcast episodes on your website.
If you see an unexplainable increase in listens from website referrals in your show's Insights dashboard, it might be due to a pre-loading implementation, so it's worth checking your website.
How about downloading a version of the episode file to our systems and playing listens from there?
Your website should be making requests to Acast’s servers for each listener, to ensure we can track data and monetise each listen.
By delivering all audio files from Acast’s servers, we’re able to track statistics for shows across all platforms — from your website, but also from Apple Podcasts, Spotify, and other podcatchers. We can then surface this data in your Insights dashboard, all in one place.
Acast also dynamically inserts advertising into episodes, depending on the time and location of the listen. To maximise revenue and avoid using a single episode file with ‘stuck’ ads, all requests should be made to Acast servers for a new episode file with fresh ads.
What about the Acast embed player?
The Acast embed player does not allow pre-loading. Using the Acast embed player on your website has several additional benefits beyond ensuring accurate data, such as collecting listen-through rate (LTR) data and in-built sharing tools. You can find out more about the Acast embed player here.