Ok, lets look at this systematically:
1) has this setup always exhibited this problem?
2) if not, what has changed?
3) can you play another source (CD, tape or record) that does not annoy? (This would determine if the DVD player is the problem.)
Assuming your Axioms are not damaged(I will leave that for Ian to discuss with you), you mention the receiver, and allude to DVD as being the source. Your amp section is fairly robust and not likely to be the cause of problem if it is functioning properly. With the BIG assumption that your amp is not damaged I would suspect your source, as DVD tends to be harsh, especially if the product is less than optimum. Do you have access to another source? Can you play a record, CD or tape with different results? Have you ever had DVD playback without this problem?
A last item could be the room acoustics.
I would doubt that another, higher quality amp would solve the issue.