Help with TS3 on ipad pro

I have a virtual server on a windows 10 pc and I connect from my w10 laptop, someone I chat with is on an ipad pro (it’s recent but not the latest) and is having problems with the voice level of different people, some too high, some too low.
I have the android app and on both the android and pc versions there is an option to individually change the volume of other users by long pressing or right clicking on that user.
How is this done on ios and can someone post any screenshots to help ?

Thanks in advance

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