Small HTML5 Audio Delay on iOS 12

Hi everyone, I’ve got a language learning app with thousands of small mp3 files that are stored locally and play on button taps. I recently updated my iPhone to iOS 12 to make sure that everyone is functioning as expected and noticed that the audio has a small but noticeable (200 or 300 ms?) delay after the tap registers. All of my other buttons function fine and respond immediately, but this seems to be the only difficulty. Does anyone else have experience with this and have a fix?

Ionic info output:

cli packages:

    @ionic/cli-utils  : 1.19.2
    ionic (Ionic CLI) : 3.20.0

global packages:

    cordova (Cordova CLI) : 8.0.0 

local packages:

    @ionic/app-scripts : 3.1.9
    Cordova Platforms  : android 7.1.1 ios 4.5.5
    Ionic Framework    : ionic-angular 3.9.2

System:

    Android SDK Tools : 26.1.1
    ios-deploy        : 1.9.2 
    Node              : v9.3.0
    npm               : 5.6.0 
    OS                : macOS High Sierra
    Xcode             : Xcode 9.4.1 Build version 9F2000