A worker at the Sinsheim club admitted to placing speakers beneath the bleachers and playing shrill sounds to drown out visiting fans on Saturday
A statement on the official Hoffenheim website revealed that the unnamed employee wanted to use, in his own words, an 'antidote' to counter the slew of insults Dortmund fans used against the village club's owner Dietmar Hopp.
He is said to have placed speakers beneath the bleachers in the visitors' block and played high-frequency noise.
The statement indicated that the employee considered the noise a joke and Hoffenheim officially apologised for the incident, but the scandal may have severe consequences for both perpetrator and club.
Speaking exclusively with Goal.com Germany, Dortmund fan Jens Volke revealed that the loud, shrill noise had caused a fellow BVB supporter physical damage.
"We will not lodge a complaint [together], but one of our fans has filed charges. He says he has probably suffered from tinnitus," Volke said.
The Heidelberg Police Department has launched an investigation, as has the DFB (German FA).
"Right now we are running a preliminary investigation to clarify the exact facts. Then it will be decided whether legal proceedings will be initiated by the control committee," DFB media chief Ralf Kottker said on Tuesday.
The shrill tones only added to the misery for BVB fans, who watched on Saturday as Sejad Salihovic's lone strike was enough to lift Hoffenheim to a 1-0 victory.