The most common and most likely answer to this crossword clue is the 4 letter word BUZZ
B
U
Z
Z
More clues leading to the result BUZZ
Buddy explains!

The straight part
We know that "Call" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case call = buzz.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does BUZZ mean?
BUZZ noun- A continuous, humming noise, as of bees; a confused murmur, as of general conversation in low tones.
- A whisper.
- The audible friction of voice consonants.
- A rush or feeling of energy or excitement; a feeling of slight intoxication.
- A telephone call or e-mail.
- Major topic of conversation; widespread rumor; information spread behind the scenes.
- To make a low, continuous, humming or sibilant sound, like that made by bees with their wings.
- To show a high level of activity and haste (alluding to the common simile "busy as a bee"). Often in the colloquial imperative "Buzz off!"
- To whisper; to communicate, as tales, in an undertone; to spread, as a report, by whispers or secretly.
- To talk to incessantly or confidentially in a low humming voice.
- To fly at high speed and at a very low altitude over a specified area, as to make a surprise pass.
- To cut the hair in a close-cropped military style, or buzzcut.
- To drink to the bottom.
- To communicate with (a person) by means of a buzzer.