Just have a look through this forum, there's a couple of threads on the subject including the following:
http://ubb.outlawaudio.com/ubb/ultimatebb.php?ubb=get_topic;f=37;t=000029
http://ubb.outlawaudio.com/ubb/ultimatebb.php?ubb=get_topic;f=37;t=000058

There's also this one, that is somewhat related:
http://ubb.outlawaudio.com/ubb/ultimatebb.php?ubb=get_topic;f=37;t=000049

I don't think it's really a "problem" so much as a power limitation of a 60w x 7 receiver. Basically it indicates that, depending on your speakers, you may need to set the volume to maximum to achieve "reference" levels.