Pitot specification?
Has anyone access to the specification of the pitot system fitted to the A330?
Could it be that the difference between static and dynamic pressure at airspeed deltas of <60 knots is 'out of spec'? Somewhere in the past, I believe I read something related to pitot design and the issues of drain holes... or at least less accurate.
The presence of the drain hole effectively reduces the low speed sensitivity, since some of the sensed dynamic pressure is bled via the drain (or something like this). There is compensation for this effect, but at some point that gets iffy.