Ticking Sound from Instrument Panel 2010 LV LX

[Kostagone]

Recently had AC Compressor replaced with new compressor. Since then there is a clicking sound coming from the vicinity of the instrument panel but only whilst the the air conditioner is on. The click dissappears on idle but reappears when the revs are increased. All dials/speedo operate normally. No clicking when the aircon is off.

Local Ford dealership and NRMA workshop dont know what this is.

Grateful for any advice before I have expensive investigation with dash removal

2010 Focus LX LV Mk11 Sport