When the following query is executed against the Master database it appears in Change Auditor as depicted in the screenshot:
USE [master] GO ALTER LOGIN [ChangeAuditorTest] WITH PASSWORD=N'XXXXXX' GO
This is expected behavior if you record the same command being executed using SQL Profiler the "Text Data" appears the same with the hyphens. This is likely intentional masking of sensitive data by Microsoft.
The product is working as expected and is presenting the data in the format received from SQL.