overquiet
/ɒvəˈkwɪt, -ˈkwɪt/Definitions
1. adjective
making too much noise and disturbing others
“The overquiet crowd at the library disrupted the quiet atmosphere.”
2. adverb
very quietly, but in a way that is annoying or disturbing
“The overquiet movement of the thief did not go unnoticed by the security guard.”