Hm, that doesn't sound right. Music and blank audio doesn't require a speaker change. Maybe some new reviewers are misinterpreting the rules?
One thing though, [APPLAUSE] DOES require a speaker change. According to the guidelines: "Use speaker changes with ccc (for COUGH), lll (for LAUGH), aaa (for APPLAUSE), etc." (This has always been in the rules)
A correct example: [APPLAUSE] [BLANK_AUDIO] >> Let's give a big welcome to our next speaker, Jane Smith. >> [APPLAUSE] >> Hello.