With the following settings I get sometimes AF beeps (like AF confirm beeps) in HDR mode between the shots, even when the lens is switched to MF. I can't find any pattern for this, so it's random... Happens with other lenses too... Canon's default AEB has no problems.
Canon 7D v2.03 + ML Advanced Bracketing Bracket Type: Exposure (Tv, Ae) Frames: 9 EV increment: 1 EV Sequence: 0 + ++ 2-second delay: OFF (Using Canon's 2 second delay by AF Drive Button) ISO shifting: OFF Post scripts: OFF
Starting value is: -4 EV