Recirc air not blowing - intermittent

[Bluefish7]

2010 X5, on fresh air the fan blows just fine (its not wind driven air only) but on recirc I can hear the doors moving and shut but very little air coming out on full blast. Air is directed to come out of the main vents and those functions seem to work well on fresh air. As far as I know the filter is fine and not the source of the depleted air flow but will check. I will say that periodically the recirc will blow a good amount of air like the blend doors sit right every once in a while. Any recs?