Based on my ( maybe wrong.. ) experience, I feel that in the case of (по)звонить only, there is a strong tendency as below.

- in most cases несколько раз звонил is used, несколько раз позвонил is very rarely used.
- in most cases два раза позвонил is used and два раза звонил is very rarely used.

I checked on the Internet and the result seems to correspond to my experience.

As to other verbs like (по)стучать, I was not able to find such tendency.

Please advise!