We have similar issues with DD in the car seat - she absolutely hates it and screams herself senseless its awful because we HAVE to drive everywhere as the nearest shop is 10km away
When we have had DD out at the shops we popped her in the bassinette attachment so she couldn't see too much and found that works the best.

I was thinking a prob we have had walking here with the pram is it jiggles far too much so we found by letting the tyres down just a smidge helped with the vibrations. Maybe try that too?

Nae x x