On various occasions in the Old Testament, God chose to communicate audibly with individuals. God will always find a way to make contact with those who want to know him. Some of those occasions are listed here.
Confronted them about sin
Gave him directions about building the ark
Commanded him to follow God’s leading and promised to bless him
Tested his obedience by commanding him to sacrifice his son
Permitted him to go to Egypt
Sent him to lead the people out of Egypt
Gave him the Ten Commandments
Pronounced judgment on a family conflict
Promised to be with him as he was with Moses
Chose him to be his spokesman
Sent him to the people with his message
Encouraged him to be his prophet
Sent him to Israel to warn them of coming judgment