Adapter Bottlenecking internet

Ever since I got the A6210 adapter for my desktop, I've noticed constant bottlenecks to my internet speed. I get 100 Mbps download with charter on the 5Ghz channel through a Netgear R6300v2 router charter gave me. The adapter is 3.0 USB and is connected to a 3.0 USB port on my desktop. I can say that it isn't my ISP because I get 70-100 Mps down on my laptop, and I've also hard-wired my desktop to the modem and I got 70-100Mps down as well. It has to be the adapter but I have no clue why. This bottleneck happens at least 4-5 times a week. Sometimes it's for 30 minutes, a few hours, or the whole day.