Forgot to add I am mining scrypt; I assumed OP was too, given the hashrate.

OP, 27kH/s is much too low for bitcoin. However on the bright side according to the hardware charts, you should be able to get up to 20MH/s with that card if you tune it correctly.

Are you trying to overclock your card? I have had high rejection rates before because I overclocked my card too much and it was unstable.

I'm having a somewhat-similar problem, my miner is chugging along at around 25kH/s, but it keeps hitting "Stratum detected new block". It's only actually tried to submit work twice in the past hour or so. I'm wondering if 25kH/s is just too slow, which may affect you too buddy