Woah, hold on before you spend money on anything. Eliminate hardware first. It’s the most cut-and-dry. Try it on the same network cable as your working desktop machine. If that works fine, it couldn’t possibly be the software and must be your networking hardware. Then try surfing wirelessly at a Starbucks. If that works fine, you know it’s the AP and you should look for firmware updates. If surfing is screwy on the network cable, you know you it’s not the AP and we can go on from there. As a famous fictional detective once said, eliminate the impossible and all that’s left, no matter how improbable, is the truth.