Grinding/vibrations whilst on pedaling on turbo

Hi All - Apologies if this is the incorrect forum to post this query.

I have recently bought a Tacx Flux 2 indoor trainer and I have a Shimano 32T cassette on the trainer.
My bike has a 11-30T cassette and shifts/pedals smoothly, however when I put my bike onto the turbo using the thru-axel conversion kit, there feels like a grinding/vibrating whilst pedaling and the shifting becomes pretty rough.
Is this a case of adjusting my derailleur to the new cassette or is this to do with how it is mounted onto the turbo? - For reference, I ride a giant propel advanced 2 disc 2020.
Thanks in advance.

That’s one possibility.

Another possibility is that your chain is worn out and stretched vs a fresh chain. Putting a clapped out chain on a brand new cassette will also make a racket. When’s the last time that chain’s been replaced?

Funnily enough… Never - only done circa 600 miles since owning it.
Wondering whether its worth just forking out for a 11-30T cassette and putting that on instead, as well as replacing the chain?

That would save a lot of hassle

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Check to see if your RD can accommodate the 32-tooth cog. They can come in various sizing for cassette usage. Depending on the model, the cutoff might be at 28 or 30 teeth. Might need a Medium size RD. And adjust the B-Screw. Going from a 30-tooth to the 32-tooth the pulley might be too close to the cog.

Maybe some dumb questions. Does the cassette on the trainer have the same number of cogs as the one on the bike? Depending on the cassette do you have spacers fitted?

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