BlackWidow Chroma X spacebar issue

Recently started getting issues with the space key on my BlackWidow Chroma X, it doesn't recognise all my keypresses.

I've checked under the bar and it's clear of obstruction and the behaviour also happens when directly clicking on the switch, my unit is now out of limited warranty (of course), does anyone have any tips on how to resolve this? The other keys are all working perfectly.

Unfortunately I can't find the heatmap applet in Razer Synapse 3, so no idea how many clicks the switch has endured, but I've had it since June 2016.

Here are some test sets of 10 consecutive spacebar presses:
3 6 8 10 9 10 10 9 10 10 9 10 10 4 8