I had a similar experience, https://developer.apple.com/forums/thread/715488. The way i fixed for myself was not to do anything, let the user manually select on the UnHold and then configure the audio session when performSetHeldCallAction is called.
raosan
Users receive reputation points by contributing quality content to the forums.
Posts include post and replies published on the forums.
Post authors can mark replies as Accepted to indicate successful solutions.
Apple Developer Forums admins can mark replies as Apple Recommended to indicate an approved solution
From
Bothell, WA, United States
Post
Replies
Boosts
Views
Activity
Scenario 3 I have figured out that if performSetHeldCallAction with onHold is true, does not respond with action fulfill (or action fail) within roughly 5 seconds then performEndCallAction is called. This makes sense when incoming PSTN call needs to be accepted asap. For us as of now the stopping of audio and performing the hold operation does go beyond 5 seconds.
I dont have any extra files still have the same problem as @pallavimh