Can i access slowmotion in underwater mode?

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Both can be accessed before putting into the waterproof case and seem to work but once in the case the setting can't then be altered unless taken out of the case again, effectively keeping you in slow-mo mode.
As shooting modes are changed via the touch screen no setting can be changed once set inside the waterproof case.  You are effectively just stuck with an on off switch.
The product page states that [ The camera cannot be adjusted when used with the waterproof case.]
Water proof case specs

Slow motion is essential whilst recording marine life