Bundu, 26, who bookmarked his eleventh appearance since joining the club, was substituted in the 57th minute.
The host started brightly after a spot-kick scored by Stephy Mavididi set the Foxes on their way to maintaining their lead in the standings.
Patson Daka, who marked his first start of the season for Leicester City, scored the second goal as the Championship leaders thrashed Plymouth Argyle.
Stephy Mavididi scored his brace from another penalty call in the 52nd minute before Wilfred Ndidi completed their win three minutes later.
Three goals were scored in six second-half minutes, Daka, Mavididi and Wilfred Ndidi 49, 52 and 55 minutes, respectively, as the Foxes ensured they remained one point clear at the summit in style.
Miller and Bundu were replaced by Ryan Hardie and Brendan Galloway. Argyle mustered some attacking impetus but was too late for any consolation.
However, Azaz stretched the Leicester defence as Jan Vestergaard snuffed out the danger with a well-timed challenge.