Murmuring: Aaron
Source: TTT
Numbers 12:1, 2, 8
Then Miriam and Aaron criticized Moses because of the Cushite woman he had married, for he had taken a Cushite wife. / “Does the LORD speak only through Moses?” they said. “Does He not also speak through us?” And the LORD heard this. / I speak with him face to face, clearly and not in riddles; he sees the form of the LORD. Why then were you unafraid to speak against My servant Moses?”