My hot end is kraken, but I think v5 and v6 are all similar. My kraken works great with PETG and HIPS, but always jams with PLA and PVA. I tried every method found here, and the only way helps is seasoning, but it dosen't last for long. So I just add a contineous oiler before the extruder. It won't compromise filament bite of extruder gear teeth, and can lubricate all the way from tube to nozzle. I don't have any jamming after this setup for 1 week, now I can print with PLA + PVA.
That's green sponge soaked with canola oil. I found it on thingiverse. http://www.thingiverse.com/thing:533276 I scaled it to around 152%, and screwed in 2 plastic connectors sent with kraken. You don't need those connecters and can do just well with original size, I just want to make it look better. For PVA, don't print too fast, stay bellow 30, or it will jam around extruder place, although I already modified my extruder for soft filament.
