So here's my situation... My ISP's package that I have advertises speeds of 12-25 mbps. I average 21, but on occasion I exceed 25 (just barely, like 25.38). I'm currently renting their Router Modem combo (which I've read is one of the worst) for $7/month. First of all, how is that possible to exceed their advertised limit? And second of all, does that mean I don't need a new router like an AirPort Extreme? I've only been looking into one because my AirPlay Speakers (Beoplay A8) requires lots of bandwidth and occasionally cuts out. Thank you so much for your help in advance!