John? You don't sound like John. Do you have a cold? Be wary of scam callers impersonating family members.

It would sound fine to say either, “Sorry. It doesn’t sound like you”, or “Sorry. I didn’t recognize your voice.” I agree the most logical statement would be, “Sorry. I didn’t recognize your voice.” You could also make a joint statement, “Sorry. I didn’t recognize your voice; it doesn’t sound like you.”

It depends on whether you want to say It did not sound like you, initially, but now I know it is you or You are not John. . Most likely is my first meaning, as others have assumed below.

The version of Jim's reply that seems most likely is the third, but the tense should be changed: "Sorry, I didn't recognize your voice." The "action" has happened: John spoke and Jim did not recognize him. Now Jim is telling John that he did not recognize his voice. The first choice "Sorry, it doesn't sound like you" might be said. Again, it would probably be put in the past tense: "Sorry, it didn't sound like you." But usually one apologizes for one's own actions. Jim not recognizing John's voice is Jim's action. If John doesn't sound like he usually does, Jim has not done anything to apologize for. This wording is also a little awkward: what is "it" in "It doesn't sound like you"? If one is listening to a recording of someone's voice, we might say "it didn't sound like you", where it is the recording. Talking to another person, one is more likely to say, "I didn't recognize your voice." The second choice doesn't make sense in English.

Jim: Uncle John?? Sorry, I didn't recognize your voice. You sound different.