I you have adequate ports and are satisfied with your WiFi performance, you do not need a switch. No switch, regardless of their claims will make better zeros and improve your 1s. Those who make that claim are preying on the ignorance of their customers. Noise is the enemy of sound quality, certainly, but digital, or quantization noise occurs in the analog to digital conversion process as a function of accumulated rounding errors that result from mapping a near infinite dataset into a finite space, e.g. 16 bits deep sampled at 44.1 KHz (CDs). And that has nothing to do with the Layer 1 and Layer 2 data transmission that is Ethernet, wired or wireless. Other noise, from cheap power supplies or poor analog circuit noise rejection, for example do not exist in the digital realm unless they preexist in the input signal and are quantized in the ADC process. Again, nothing to do with Ethernet.