Answer: 'making that noise' is the complete gerund phrase in the sentence 'Please stop making that noise!'.
A gerund is a word which is formed by a verb but acts as a noun. They are formed by adding '-ing' at the end of a verb. Whereas, a gerund phrase begins with a gerund (a word ending with '-ing') and comprises of other objects as well.
Here in the given sentence, 'making' acts as a gerund, 'making that noise' is the complete gerund phrase and it is used as a direct object.