slight vibration/shake in steering wheel on 2005 Honda Accord

I have a 2005 honda accord v6 done 70000 miles.I have done wheel alignment,wheel balancing(front) and the tyres are in good shape. Sometimes when i make a turn and the steering wheel comes back to the normal position it shakes left right .It doesnt shake violently.Also when i am at high speed sometimes i can see the steering wheel vibrate, not like the vibration due to an unbalanced tyre.
Can someone tell me the cause of this or you need more information on the problem,

Asked by for the 2005 Honda Accord
I have similar problem. I just bought the car and the dealership i bought it from (Honda) promised to take care of it but it seems like they can't find the problem. this is the second alignment and 2 days ago they install a set of brand new tires...however I feel it is the motor mounts or the converter since I feel slight vibs in a stand still too. please let me know if you found a solution and I'll let you know what they say tomorrow.
Similar problem same efforts. They traced
my issue to front axl vibration. 1000 to repair.
Strange thing is that if the tyre pressure is low i feel the vibration but once i fill it the vibration disappears
they install new axles and still the same. i gave-up at this point. i'll drive it like that.