You need to manage preferredForwardBufferDuration avplayer currentItem. If you want to stop the set buffering value to 1, because if you set it to 0, it will be automatically configured
self.avPlayer.currentItem.preferredForwardBufferDuration = 1;
From Apple documentation: This property determines the preferred forward buffer duration in seconds. If set to 0, the player will select the appropriate buffering level for most use cases. Setting this property to a low value will increase the likelihood that playback will stop and re-buffer, and setting it to a high value will increase the demand for system resources.
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