NotHardUp1
What? Me? Really?
Several news outlets said it was a suspected heart attack so I don't think anyone can be blamed for following that line of thought. Much better than speculating on other, more salacious, causes
Short of an autopsy, it sounds like a) baseless speculation, or b) potentially intentional misinformation if family or friends were creating a rumor to deflect from drug abuse or suicide.
There have just been too many times when family, friends, or even an artist's label, hid the real cause of death to protect a reputation for commercial purposes. Until an official statement is made by a coroner or the family, there isn't any better or worse in speculation. As long as no cause is forthcoming, the possibilities are anywhere between an undetected natural cause all the way to suicide or murder. Unlikely is unlikely, but as long as people don't know, they speculate.

