Welcome to the SeeMeCNC Community

I just changed my retraction settings, to match some I found on the Slic3r site, as an experiment. They are now ;

Length : 1mm

Lift Z : 0mm

Speed : 30mm/s

Extra length on restart : 0mm

Minimum travel after retraction : 2mm

That's quite different from what they were before (SeeMeCNC defaults)

What retraction settings are you using? If you've got the time to post your retraction settings here, that'd be great.

Actually those were no good - I've gone back to defaults

Those are probably for a direct extruder rather than a bowden one.
I use 2mm at 40mm/s on my kraken, and on my E3D V5

Yes, they didn't work too well.

Now I've switched to Cura, and am using 40mm/s & 4.5mm