ANSWER:

No problem in replying to the adhan but you must not pray behind such people and you must attend the congregation in the salafi masjid.

QUESTION: Can i follow aadhans from mosque who rejects sahih hadiths or mosque which does shirk. I am in a locality where i have two mosque near me both the mosque either does shirk or rejects sahih hadiths (eg: Rejecting hadith and believing a spell does not casted upon mohammad s.w.t). or should i follow the salafi mosque (far from my home but has a app that sync aadhan time)