A bit of CRM... turn the horn horn horn HORN HORN HORN off so you could think more clearly.
Why turn the horn off? What if you then had a HYD issue? (however highly unlikely) You have no audial warning of that emergency then all of a sudden your accumulators have run out. Perfect time for that to happen when your low to the ground. Or at any time.
I would leave the horn on, as its only showing High RRPM tones, then it will also let you know if HYD or low RRPM situation happens.