It's impolite to mutter to one another in class.
Actors often mutter to themselves when rehearsing their lines.
With tears in his eyes, he would watch them Wolf it down and mutter to himself, "Poor motherless children!"
The youth likewise went his way, and once more began to mutter to himself, "Ah, if I could but shudder!"
If I look at the Cartesian, I did have the Cartesian form, don't mind while I mutter to myself here quietly.
He suffers from serious bouts of spousal deafness but never fails to hear me when I mutter to myself on the other side of the house. "What did you say?" he'll shout.
