Makita EA4300 surging at idle

[Hulsty]

As per the title, last week I took out my EA4300 for some firewood cutting while camping and I noticed between cuts the saw was carrying on and surging/speeding up at idle. In the cut at WOT rpm was consistent and how it has behaved in the past. I stopped, cracked the fuel tank cap and no more issue. What/where should I be looking to sort this out ? Saw itself hasnt done much work, I would say less than 15 full tanks through it.

 

[HumBurner]

Vent and lines

 

[Hulsty]

Thanks, I will have to check out the IPL