The interior noise and thermal performance of the passenger compartment are critical criteria for ensuring driving comfort [1]. This paper presents the optimization of air conditioning (AC) compressor noise, specifically for the low-powered 1.0 L - ICE engine paired with a 120 cc IVDC compressor. This combination is quite challenging due to the high operational load & higher operating pressure. To enhance better in-cabin cooling efficiency, compressor’s operating efficiency must be improved, which necessitates a higher displacement of the compressor. However, increased displacement results in greater internal forces which leads to more structure-borne induced noise inside the cabin. For this specific configuration, the compressor operating pressure reached up to 25 bars under most driving conditions. During dynamic driving scenario, a metallic tonal noise from the compressor was reported in a compact vehicle segment. It is reported as very annoying to passengers inside. A comprehensive root cause analysis was conducted, including Transfer Path Analysis (TPA), evaluation of compressor fixation points stiffness, and dynamic noise signature analysis. The investigation revealed that the metallic noise was a combination of moaning and whining sounds, primarily caused by internal excitation forces within the compressor. These forces generated dominant excitations at high operating pressures, resulting in the observed tonal noise. Several countermeasures were explored, including changes to the compressor pulley ratio to decouple engine firing frequency excitations, modifications to the AC pipe bends to reduce excitation forces, and optimization of acoustic mass and compressor mounting stiffness. Collaboration work has been done with the supplier focused on fine-tuning the Mass Flow Control Valve (MFCV) settings [6] and adjusting compressor shaft tolerance. The most effective solutions were the compressor pulley ratio change and the modification of the compressor’s planetary plate angle, which together achieved an improvement of approximately 6 dB(A) in compressor order noise, significantly reducing customer-perceived annoyance. As a result, key NVH (Noise, Vibration, and Harshness) design rules have been established and implemented