Noisy cassette on new wheel

[Spudmaster]

Hello

Just set my new DT Swiss P1600 wheels up and headed off for my first ride, only to be met by the mother of all rattles every time I go over even the slightest of bumps.
The wheels came with the spline to fit a Shimano 10 or 11 speed cassette; and I fitted a new Ultegra 11 speed. (My old wheel & cassette being kept for turbo trainer.
Pretty certain that it is a loose cassette that is causing the news. Is it just a case of inserting additional spacers, or am I going to need to send the wheel back?

Any pointers much appreciated!
Cheers
Spud

[frisbee]

No typical worn chain noise but just a rattle going over bumps?

You shouldn't need any spacers for an 11 speed wheel and 11 speed chain. If you've left off one of the plastic spacers the sprockets will be really loose.

[Castrol for a knave]

It could be lacking a spacer, but it could also be your end, smallest cog. Sometimes if it has not set properly it can rattle the cassette.

try re-seat it - often it seems to have dropped into place but hasn't, so the locking ring can't bind up the cogs onto the hub.

[gazza285]

I’ve had to use a spacer on an eleven speed cassette before, the lock ring was thread bound before nipping up in the sprockets. Shimano cassette on one of the better Novatec hubs.

[Spudmaster]

Just done a bit more research, and it appears that the 11-34 version of the Ultegra cassette requires a spacer at the back.
It should have been delivered one, but it appears I might have lost it, (too late to prove it was not included).
Replacement coming from Wiggle for £2.84...
Thanks for tips!
Spud