I’ve experienced various problems like missing downlinks (device with confirmed uplinks has to repeat too often), poor sensitivity or bad reception (especially when only CRC valid packets are forwarded), inability to operate on DR7 or even gateway getting stuck.
are you using internal antenna or external? because external sma was connected by default and I needed to open it up and switch the antennas connectors to proceed with internal.
this is mikrotik’s reply on that issue (high rcvd/transmtd frames): We will fix this in upcoming versions of RouterOS. I will inform you, when the fix will be ready.