Hello.
I am trying to determine what causes this but, so far, I have being unable to. I am pretty sure this happened to me before the 1.03 patch too.
Description:
Your created PC/companion will be muted (i.e, no barking sound when clicking on his/her portrait) if your party is already made up of six characters.
Steps to reproduce.
Fill up your party with six characters. I believe I created my main char and another one and then I added up three characters you can recruit on several maps (Aloth, Edér, Durance and/or Kana).
After creating a new character and swapping her for Aloth, she is utterly muted. Not a big deal but annoying.