leave (one) cold
To not affect one; to bore or underwhelm one. A noun or pronoun is often used between "leave" and "cold." The presentation had some nice points, but in general it just left me cold—it needed something to keep up interest.
leave one cold
Disappoint one, fail to interest one. For example, This book leaves me cold. This expression, first recorded in 1853, employs cold in the sense of "unenthusiastic" or "indifferent," a usage dating from the late 1100s.