When I browsed through my error logs to check for another problem, I came across this error on a few occasions that appears to be related to the module:

[client 81.224.211.79] PHP Notice:  Undefined index:  Item in //modules/eez_amazon/mod.eez_amazon.php on line 321

Also, this one showed up once:

[client 81.224.211.79] PHP Notice:  Undefined variable:  chunk in //modules/eez_amazon/mod.eez_amazon.php on line 516