Acapela TTS Speaker not working

Issue

TCECP and VoiceLink fails to start when one of the Acapela TTS Voices is activated.
Everything works fine with the default Microsoft voice.

Cause

The registry key TCECP\TCRT\TTS\Sapi5Path shows following value before installation of Acapella:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Speech\Voices\Tokens

After installation of Acapella, following value is shown:

HKEY_CURRENT_USER\SOFTWARE\Microsoft\Speech\Voices\Acapela TTS Server 8.0

With the second value, also the Microsoft TTS does not work anymore, while when switching back to the first value, Microsoft TTS works again.

We also get an eventlog Error ID 30014 "Init TTS-Engines Failed"

Even using the Acapella test tool, with the function "Save as.wav" creates an error.

Solution

The problem with the Acapella test tool is known problem with some version on servers without sound card (which is most common on virtual machines). However, this was not the source of the problem – the Acapela TTS Server should work and is not depending on a sound card.

The solution is to change TCECP\LogonType from Batch to Service. It seems that a process running in Batch mode cannot initialize SAPI5 with Acapela. This is from own testing and not confirmed by Acapela yet.

It is also a requirement in my environment that TCECP is started by TCSRV with a Windows user account (TCECP\UserId and Domain).

Finally, TCECP\TCRT\TTS\Sapi5Path must be

HKEY_CURRENT_USER\SOFTWARE\Microsoft\Speech\Voices\Acapela TTS Server 8.0

The last very important point is to login using the account specified in TCECP\UserId in order to create the desktop environment etc. Simply creating the user and assigning “Log In as Service” is not enough.

Level of Complexity 

Moderate

Applies to  

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