What kind of pump are you running from the return? Depending on the pump you may have no option but to live with the noise as this is where price differences come into play. Less expensive pumps are usually louder, run hotter, and consume more electricity whereas higher end pumps are quiet, cooler, more energy efficient and some are even rebuildable.
Are your overflows hang on or drilled. If the tank is drilled you can build a durso or internal pvc coast to coast overflow, or if you have multiple holes you can design a bean-animal.