While the efficacy of high end powercords and interconnects may be debated among novists and value oriented audio consumers, it is not debated among seasoned audio enthusiasts, high end designers, dealers and audiophiles. A high quality system cannot perform near its potential without optimizing all the components and all the wires are components in the system. It is important to have all optimized, compatible and synergistic boxes, then move on to the wires that connect them and provide power.
I would recommend trying a Cardas Clear Beyond and AudioQuest Hurricane. These will both provide instant easily heard improvement of very different flavors. One will likely appeal to you more.
A couple comments. When we refer to noise or the noise floor, it is not about hiss or audible directional noise. It is about the background… it is how black and void it is. Not even consumer products should have noise in the traditional audible sense. It takes some time listening to systems to train your ear to recognize the noise floor. More details emerge as the floor drops, the sound is more dynamic you feel more relaxed instead of jacked up by the music. This is one of the characteristics wires improve.
To this end, I recommend a better power cord, but also plugging your integrated via high end cord directly into the wall. Amps perform much better this way, and yours is likely to. But since it is an integrated… maybe not.
A big boost in sound quality also comes from running direct lines from your breaker box. Typically one for your amp and one for your power conditioner / other components.
Sounds like you have opportunities for two substantial improvements at least.
