It is a little known fallacy with WiFi that a stronger signal always makes a better connection.
Try tuning your Access Point down so that your Duet only sees -60 to -72. What happens is that the AP is "shouting" so loud that it can't "hear" the Duet talking back. This is a common problem in business WiFi with Apple products. The Apple products are designed with a low output strength to conserve battery strength.
This is an easy fix and may explain why you and DC42 are not seeing the same behavior.
Of course, it may not, but it's worth a try.