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If you have a trigger box trigger an ambient audio clip when you enter the box, the audio clip will always play from the beginning even if you have the Start time starting later in the audio clip.
Tested on an iOS iPad Air 2 (8.1) and an NVIDIA Shield Tablet.
1) Open a new First Person Template Project (Include starter content)
2) When the level loads, Create a new Ambient Sound Blueprint
3) Set up the Blueprint as shown in the Photo attached.
4) Once complete be sure to Compile and save the BP
5) Drag that BP into the Viewport to add it to the level (Be sure to uncheck the Auto Activate button)
6) Place a trigger box into the level.
7) Setup the level Blueprint as it is shown in the photo attached
8) Once set up, Play in Editor and you should notice that the sound will start halfway through audio clip
9) Deploy the project to a mobile device
10) Once deployed, Open the project on the device and enter the trigger box to trigger the audio cue.
Head over to the existingAnswerHub thread and let us know what's up.