Before any adjustment, please check your pool filter is clean and there is no debris in your Pump basket.
With your Automatic pool cleaner properly adjusted, SkimmerMotion should have the required suction to operate at optimal level.
After initial istallation you will need to increase the suction power of your system, increasing (a bit) the valvle that control the suction line (located near the pool Pump).
Inside the basket of SkimmerMotion you will see 3 dots you need to alight with the base in order to set the Whirlpool suction power. #3 is the lowest suction power and #1 is the strongest one. Usually setting #2 is the optimal. If you set your Skimmermotion to #1 and make noise is an indication of too much suction level and is not recommended since it will trap air into your pool system.
Here is the recommended adjustment: Using your APC manual, with the SkimmerMotion power setting in #3 (basket), adjust your APC for optimal performance. Usually there is a flow meter to reach the optimal level. Then move SkimmerMotion (SM) Power Setting to #2, it should work fine with enough suction to absorb bugs, debris and small leaves.