Chain skating on small chainring

[David Marshall]

On my road bike I have a shimano 105 10sp with a FSA Gossamer crank.  When changing from the large to small chain ring I sometimes get the chain riding on top of the small ring, while resting against the large ring.  This does not happen if I am on any of the lowest 3 gears on the back but usually when in 5 or 6, where I normally change when going through a dip.  While surfing the web for the problem I found that this occurs when using a 9 speed large chainring (marked S9,C10) instead of the ten speed S10.  Problem is my chainring is marked S9.C10.S10 so I assume it is suitable for both 9 and 10 speed.  Anyone had this problem or is using a similar ring with a ten speed?  Would the chainline influence this?  The rings themselves are in good nick.

 

I have emailed FSA on the ring suitability but still wait a reply.