That's not a theory, that's some kind of urban legend or folklore, and it's nonsense. Repeating it without a shred of substantiation is equally nonsensical.
If you want to "stay way from Volvos" on account of it, fine. Please also consider throwing a pinch of salt over your shoulder when you spill it, and crossing the street when you see a black cat.
If you want to "stay way from Volvos" on account of it, fine. Please also consider throwing a pinch of salt over your shoulder when you spill it, and crossing the street when you see a black cat.