Same issue here too, I found that dropping the wifi from my computer then rejoining usually fixes the issues; thereafter a power off/on of the Powerline adapted does the trick. Not at all ideal for...

Model : Hardware Version : Not Clear Firmware Version : ISP : Hello, I've a Powerline TL-WPA4220KIT which, via its ethernet, I am able to access the NAS on my router @ the other end of the house....