Hey @r1chard, have a look at this thread.
Quoting @vincent:
Elements having glitches are often provoked by animated elements overlapping them. Make sure your blinking element has a higher z-index value than the animated one, to begin with.
Quoting @DFink:
Throw this in your head tag. Fixes all the weird text rendering that happens in safari.
<style> body { -webkit-font-smoothing: antialiased; } </style>
Maybe this fixes things for you. Let me know how it goes 