FOUND THIS IN THE WN1000RP wi-fi range extender manual.
http://www.downloads.netgear.com/files/GDC/WN1000RP/WN1000RP_UM_9Nov12.pdf
Could this have a bearing on your situation ?
Interference Reduction Table
The table below shows the recommended minimum distance between NETGEAR equipment and household
appliances to reduce interference (in feet and meters).
Table 4. Interference reduction table
Household Appliance Recommended Minimum Distance
Microwave ovens 30 feet / 9 meters
Baby Monitor – Analog 20 feet / 6 meters
Baby Monitor – Digital 40 feet / 12 meters
Cordless phone - Analog 20 feet / 6 meters
Cordless phone – Digital 30 feet / 9 meters
Bluetooth devices 20 feet / 6 meters
ZigBee 20 feet / 6 meters