It seems that beta 8 can't use 80 Mhz in Band 36 or 40 in 802.11ac, it can only use 40 Mhz. But it can use 80 Mhz in Band 153. In previous beta 7, it can does that in all 3 bands. My Mac is iMac 5K. My router is Netgear R8000. Any has the same issue?