[Bug] iOS: TextToSpeech.SpeekAsync stops working after multiple uses

[baskren]

Description

TextToSpeech.SpeekAsync stops working after multiple uses on actual iOS device

Steps to Reproduce

1. Clone demo project and open in VisualStudio Mac Enterprise.
2. Build, deploy, run on iOS device (in my case, iPhone 7 Plus w/ iOS v 13.3.1)
3. Click the [Speak n Leak : 0] button
4. Wait

Expected Behavior

App should continue to speak a series of integers, incrementing by 1, indefinitely. Also, app should update the [Speak n Leak : {n}] button with the latest value.

Actual Behavior

• App stops speaking after it says "248" and also stops updating the displayed count at [Speak n Leak : 249].
• App will not speak again, even if [Speak n Leak : {n}] button is pressed again.
• In VisualStudio Mac's Application Output -Speak_n_Leak.iOS window:

2020-02-21 09:50:50.091 Speak_n_Leak.iOS[570:93131] Got the query meta data reply for: com.apple.MobileAsset.VoiceServicesVocalizerVoice, response: 0
2020-02-21 09:50:50.185 Speak_n_Leak.iOS[570:93131] Got the query meta data reply for: com.apple.MobileAsset.VoiceServices.VoiceResources, response: 0
2020-02-21 09:50:51.805 Speak_n_Leak.iOS[570:93136] Got the query meta data reply for: com.apple.MobileAsset.VoiceServicesVocalizerVoice, response: 0
2020-02-21 09:50:51.816 Speak_n_Leak.iOS[570:93136] Speech initialization error: 18446744073709547611
Thread finished: <Thread Pool> #7
Thread finished: <Thread Pool> #6
2020-02-21 09:54:36.603 Speak_n_Leak.iOS[570:94132] XPC connection interrupted

• In the console (via Xcode / Window / Devices and Simulators), the following is displayed on the console log:

default	09:50:51.816184-0500	Speak_n_Leak.iOS	Speech: Error (hex)80000012 (int)-2147483630 at /BuildRoot/Library/Caches/com.apple.xbs/Sources/TextToSpeech/TextToSpeech-372.8/NashvilleBundle/TTSNashvilleVocalizer.m:167 (couldn't initalize TTS)
default	09:50:51.817590-0500	Speak_n_Leak.iOS	Speech: Error (hex)80000012 (int)-2147483630 at /BuildRoot/Library/Caches/com.apple.xbs/Sources/TextToSpeech/TextToSpeech-372.8/TextToSpeechBundleSupport/TTSSpeechServer.m:1147
error	09:50:51.817666-0500	Speak_n_Leak.iOS	Error initializing speech: -2147483630. Perhaps the asset was bad? voice: (null) premium: 0, speech server: TTSNashvilleSpeechServerInstance
default	09:50:51.817825-0500	mobileassetd	-[ControlManager handleClientConnection:on:]_block_invoke: client: Speak_n_Leak.iOS, command: 21
default	09:50:51.817874-0500	mobileassetd	-[ControlManager handleClientConnection:on:]_block_invoke: client: Speak_n_Leak.iOS, command: 21
default	09:50:51.817903-0500	mobileassetd	-[ControlManager handleClientConnection:on:]_block_invoke: client: Speak_n_Leak.iOS, command: 21
default	09:50:51.818025-0500	Speak_n_Leak.iOS	Speech: Error (hex)80000012 (int)-2147483630 at /BuildRoot/Library/Caches/com.apple.xbs/Sources/TextToSpeech/TextToSpeech-372.8/NashvilleBundle/TTSNashvilleVocalizer.m:167 (couldn't initalize TTS)
default	09:50:51.818061-0500	Speak_n_Leak.iOS	Speech: Error (hex)80000012 (int)-2147483630 at /BuildRoot/Library/Caches/com.apple.xbs/Sources/TextToSpeech/TextToSpeech-372.8/TextToSpeechBundleSupport/TTSSpeechServer.m:1147
error	09:50:51.818109-0500	Speak_n_Leak.iOS	Error initializing speech: -2147483630. Perhaps the asset was bad? voice: Samantha premium: 0, speech server: TTSNashvilleSpeechServerInstance
default	09:50:51.818141-0500	Speak_n_Leak.iOS	Speech initialization error: 18446744073709547611

Basic Information

• Version with issue: Xamarin.Essentials 1.0.0 to 1.3.1
• Last known good version: none
• IDE: VisualStudio Enterprise Mac 8.4.5 (build 19)
• Platform Target Frameworks:
  • iOS: info.plist deployment targets from 8.0 to 13.0
• Nuget Packages: Xamarin.Forms 4.3.0.90
• Affected Devices: iPhone 7 Plus w/ iOS 13.3.1

Reproduction Link

https://github.com/baskren/Speak_n_Leak