Unexpected Language Switching in Word's Read Aloud Feature When Reading Math Expressions from Equation Editor

[brichwin]

eDAD tracking ticket for this issue is Accessibility 228590

Description:

When using the Read Aloud feature in Microsoft Word to read math expressions created with the built-in Equation Editor, the text-to-speech voice unexpectedly switches to a different language. This issue consistently occurs with specific types of math expressions and varies depending on the variables and structures used in the equations.

Steps to Reproduce:

1. Open Microsoft Word 365 (Desktop version).
2. Create a new document.
3. Set the default document language to "English (United States)"
4. Insert a "simple" fraction as a math expression using the built-in Equation Editor (e.g., using the linear Unicode mode enter x/y, then space to build up the fraction).
5. On a new line, insert a "complex" math expression using the built-in Equation Editor (e.g., using the linear Unicode mode enter (a+b)/(a-b), then space to build up the fraction).
6. Use the Read Aloud feature to read the document.
7. Observe the language switching between different math expressions.
8. Select the entire document, and use the Language -> Set Proofing Language... commands on the review tab to set the entire document language to "English (United States)"
9. Use the Read Aloud feature to read the document.
10. Observe that the language of the expressions cannot be set (there is still language switching between different math expressions).

Expected Behavior:

The Read Aloud feature should use a TTS voice consistent with a passage's indicated proofing language including when reading math expressions.

Observed Behavior:

The Read Aloud feature unexpectedly switches to a different language when voicing certain math expressions. The language change is consistent for the same expressions across different attempts.

Version Information:

• OS Version:
  -- OS Name: Microsoft Windows 11 Home
  -- Version: 10.0.22631 Build 22631
  -- Locale: United States
• Microsoft Word Version:
  -- Microsoft 365 Apps for enterprise
  -- Microsoft® Word for Microsoft 365 MSO (Version 2406 Build 16.0.17726.20078) 64-bit

Example Video and Sample Document:

I have provided a link to a short example video demonstrating the issue, and attached a sample file where series of expressions are entered, and when the document is read aloud using the Read Aloud feature built-into Word, the text-to-speech voice/language changes.

Attachments:

• Video: Unexpected Language Switching in Read Aloud Feature When Reading Math Expressions from Equation Editor (5 minutes)
• Math Expressions That Change Language When ReadAloud.docx

Additional Context:
Different math structures (e.g., complex fractions, variables raised to complex exponents, matrices, etc.) combined with different variable names (e.g., x and y vs. a and b) appear to affect the language in which the expression is spoken.

Request:
Please investigate this issue and provide a fix so that the Read Aloud feature maintains a consistent language when reading math expressions created with the Equation Editor.

[jkhurdan]

Description

I recreated the word doc using MacOS and the instructions above, along with testing the .docx file provided above.

Version Information:

• OS Version:
  -- OS Name: MacOS
  -- Version: Sonoma 14.5 (Apple M2)
  -- Locale: United States
• Microsoft Word Version:
  -- Microsoft 365 Apps for enterprise
  -- Microsoft® Word Version 16.86 (24060916)

Observed behavior

In both cases the document did not switch languages and I was unable to recreate the above issue. I will test this with Windows (as described above) but wanted to indicate that this issue was not appearing for MacOS users.

Attachments

Video 1: Recreation of steps above
Video 2: Testing document provided

Further testing will be done with Windows 11 device as described above.

[jkhurdan]

Tested this with Windows Device, and was able to recreate the above. This issue is Verified for Windows 11, Word 365 users.