The all-rounder was one of four players dropped from the third Test against India for failing to provide points as to why the team succumbed to two defeats in the series.
"They have normal difficulties that anybody has in a relationship," Sky Sports News quotes Howard as saying.
"The reality is that Michael is a strong driver and they had 18 months to work on that. But I am not going to get drawn into that conversation.
"The captain and the vice-captain have to sort their issues out. If Michael wants to raise it as a greater issue, he can come forward."