Beagle board MMC ERROR

Dear sir,
  I am using beagle board B7. and not able to get video output on dvi
as well as S-video after loading kernel (before that during u-boot
both are ok) . i have tried with kernel 2.6.27-omap1 and also 2.6.28-
omap1. For 2.6.28 there is one more problem that is i am getting
following error with mmc card so that i am not able to check video
out with 2.6.28-omap1.

  mmc0: error -110 whilst initialising MMC card

but for same card is working ok with 2.6.27-omap1.

Regards
Mital Pawar