[BUG] Playback head does not progress for audio only item on iOS (iPhone)

[elynema]

Describe the bug
On iOS iPhone, when an audio only item is played, the playback head does not progress.

To Reproduce
Steps to reproduce the behavior, including the results:

1. On an iPhone (iOS 17), go to https://avalon-staging.dlib.indiana.edu/media_objects/rf55z7692. This has been confirmed in Safari, but also reported in other browsers.
2. Click play to start playback.
3. The playback head remains stuck at the beginning, even though the audio is playing.

Expected behavior
Playback head should progress as the audio item plays.

Screenshots/Screen Recording

Screen.Recording.2024-07-23.at.10.40.23.AM.mov

Environment (please complete the following information):

• Device / platform: iPhone
• OS: iOS 17
• Browser: Safari (and Chrome?)
• avalon-dev
• [x ] avalon-staging
• mco-staging
• mco-production
• demo

[elynema]

There is a check in Ramp for iOS player put in place for really laggy seeking behavior in native player. iOS devices turns off updating of custom progress bar b/c not necessary in the native player. Because audio player does not use native player, the custom progress bar is not getting updated.

[elynema]

On avalon-dev, the playback head is now progressing in iPhone iOS17 when playing an audio only item.

@Dananji @masaball
We already have #601 for slow scrubbing on iPhone, but that issue reports scrubbing taking 3-4 seconds. I am seeing it more often at 6-12 seconds or more in the native player on iPhone. I know that initially the code that created this bug was working to speed up scrubbing in the native player, and this fix might be negatively impacting that work?

This video shows 6-10 second delay in scrubbing, but if you drag the playhead nearly to the end of the item just after starting playback, it can be longer

Private Zenhub Video

[elynema]

I did some more checking this morning, and it looks like I am seeing the longer scrubbing times on avalon-staging in iOS/Safari as well. MCO is showing more of 2-4 seconds for scrubbing, so it seems to be faring better.