Silence gets read as judgement when it is usually just nerves. Somebody who says nothing in a new group can look like they think they are above it, and people respond to that reading rather than the person, which keeps the whole misunderstanding in place. The quietest one in the room is frequently the most anxious.

Go first with somebody you have privately written off as cold, and keep it light and short. Give it a second try before concluding anything, since one encounter is thin evidence. If you are the quiet one, remember your silence is being translated, and a small hello does most of the correcting.