THE workforce at the Belfast engineering company, Mackie International, has been reduced to 28 after the receiver, Mr Tom Keenan, of Deloitte and Touche, made 20 further redundancies. Mackie is currently up for sale and last week Mr Keenan said no interest had been expressed. Of the Mackie businesses, only the electrical business subsidiary, Automatic Temperature Control, has been sold as a going concern to a group of former managers led by the chief executive, Mr Sul Sahota.