Salary to Commission-based H1B

Hi,

My H1B started two months ago. During these two months, I have been paid with prevailing salary. Now my company want to change to commission based pay. My base salary is much less than the prevailing salary and I am not sure how much commission I will be able to make. Is it going to cause trouble for me in the future when I try to extend my H1B? What I can do? Thanks a lot for any advice.