I've never had any issue with changa. I would usually add 270-290mg of freebase caapi alkaloids per gram of DMT. Most if not all of my experiences have been very rich in character and color, always with an intense grounded narrative. There's much more of a dialogue ime.
Sometimes, flavors of hyperspace come in waves. Sometimes it's all radiant glory seeping with the divine, other times your getting ripped apart by somber, calamitous forces, in the end - what needs done is what needs done (hell or high water as they say).
The worst thing you can do is feed into this, attach yourself and look into it more than is needed.
Accept whatever may come on it's own terms. Give in, fully to whatever happens, ,just smile and accept.
Just remember, whether it's trickster entities, gods, demons, or whatever other form that chooses to present themselves...it all springs forth from the same place. And remember that whatever comes forth, it shall pass. Whether 'positive' or 'negative', both are needed - the duality. A cosmic dance with it's highs and lows.
the river is wild

Thank you for you're advice ,, and you're right , whether I admit it or not I've had a fair share of stress lately and I think it's that and that alone that feeding into these tricksters or just out nasty entities because whether we like to admit it they are there in this wonderful dance as you say !
Late last night I gave it one last shot with this batch before giving it away and I must say it was the most beautiful Experiance of my life , there was no beauty in colour form is was mainly the loud high pitch noise with the most unusual vibration sensation with a euforea , along with flashes of my family members who has passed away , it was simply divine , so much so I don't think it will ever be topped off !

thank you all for you're advice I am so happy that I belong to a group ( community ) that give great advice and accually care ! Thank you