LiteOn LVD-2001 defect? (A-B function)

Hi,
I recently purchased a Lite-On LVD-2001 DVD player and while its basic
function of playing DVDs and music CDs works, the A-B function doesn't
work.

The A-B function in this DVD player was one of the main reasons I
chose the LVD-2001 over other brands, so I was disappointed to
discover that this function is not working.

A quick check with Lite-On's tech support revealed that the A-B
function is supposed to work and it seems that the problem is in my
particular to my unit only.

Since I am well within the 30-day return policy of the retailer from
which I purchased it, I have two options:
(1) Return it to the retailer (exchange or refund)
(2) Ship it to LiteOn (USA) for repair.

However, before I decide which option to take, it occured to me that
perhaps other people have encountered this problem before and maybe
there is something I am doing (or not doing) that prevents the player
for responding the A-B button on the remote control (all other remote
control functions are working!). The green LED on the remote control
flashes when I press the A-B button, but the player itself continues
playing (regardless whether its video or music) as if no button was
pressed.

Could you please share your experience?

BTW, if this A/B function works for you, does it work with both video
and audio or only with audio CDs?

Many thanks in advance!