I have the exact same problem with you.
I bought my 5711/1A in Oct.2012.
At first 2 months I didn't wear it everyday so I didn't notice any problem.
on Jan. I noticed the same with yours I start to wear it everyday.
And found out it happened almost everyday.
I took it back to my AD,they said they have to send it back for adjust and test.
Its' almost 1 month now,and my watch haven't come back.
