Under extrusion problems at solid infill

Hello everyone. So i have a problem while tuning my own prusaslicer profile. Using Ratrig V-core 3.1 500, Phaetus rapido 0.6 volcano, Bondtech lgx-lite, and the filament is Polymaker Polylite PLA. Machine has been IS, PA, skew tuned, and PA is set to 0.03 (same as default rapido profile in RatOS) The current speed and extrusion width are shown in the image While tuning the profile, i do notice the terrible solid infill and bridging performance, as the image shown. The gap of the bridging is a bit wide, but i think can be fixed by changing the bridge flow rate. But, the main issues is the solid infill, not only have large gaps between each extrusion line, but also the interrupting extrusion all the way. My guess is, there are ways to improve such problems: 1. Adjust extrusion width wider and larger overlap. 2. Slowing down the solid infill speed 3. And one supcious settings in prusaslicer, the "Max volumetric speed" under Speed page, which is set to 25mm^3/s, maybe the cause? Currently, i dunno where to start changing, hope someone can giving some opinions and advice to start with.