Edward 96 Viper GTS

my psm light is flashing sporadically when going over ripples in the road at approx 38+ mph normal dry road conditions. the front brakes/ clutch mechanism also engages causing a gring sound.
under cpo warranty. so far the dealer has done the following procedures searching for a solution
1- no codes are thrown
2- no onboard driving codes are thrown
3- new wheel sensors. no cure
4- new comuter brain. no cure
5- new brake master cylinder. no cure
6- four new tires as the cpo tires had too big a difference in circumference. no cure
as you can imagine, the dealer is very frustrated and is now going to involve POrsche north america.
anybody else experience this psm flashing, grinding problem?
tia
ed