dForce Classic Messy Bob Hair for Genesis 9, 8, and 8.1 Female odd outline?

Pitmatic

Hi

I have the https://www.daz3d.com/dforce-classic-messy-bob-hair-for-genesis-9-8-and-81-female by Linday wich i really like but in my smokey bar scene an outline appears on the hair when i use a volume to do a bit of smokey/foggy scatering

so we have linday hair with no volume cube and then with the volume cube on, notice the odd outline that has appeared and finaly a different hair in the volume (HS WW hair gen 9) it kind of looks like someones used a felt pen around her hair :)