voice communication vs speech communication

voice communication and speech communication both are nouns.

Word	Noun	Adjective	Verb	Adverb
voice communication	Yes	No	No	No
speech communication	Yes	No	No	No

As nouns, voice communication and speech communication are synonyms defined as:

voice communication and speech communication: (language) communication by word of mouth

Other synonyms of voice communication include language, oral communication, speech, spoken communication, spoken language.

voice communication (noun)	speech communication (noun)
(language) communication by word of mouth	(language) communication by word of mouth