Extra-biblical revelation

Humans could hear in a frequency range of 20 HZ to 20000 HZ. However, Dogs and cats could hear high-frequency sounds ranging up to 45000 HZ and 64000 HZ respectively. The dog whistle was invented by Francis Galton in 1976. Humans could only hear a hissing sound of high-frequency noise, while dogs could hear the dog whistle.
Revelation of God: God has revealed Himself in Creation, Word and Lord Jesus Christ. (Romans 1:20) The frequency range of God’s revelation begins from the creation and is completed in Lord Jesus Christ. In His wisdom, God has determined that this frequency of revelation is sufficient for human beings to know God, His attributes, human Fall, need for Saviour and the Saviour Lord Jesus Christ. Beyond this there is no need for any more revelation. However, there are some who could hear ‘revelation’ beyond or below the range, as dogs could hear high-frequency noises.
Counterfeit magicians: When Moses performed miraculous signs before Pharaoh, Jannes and Jambres obstructed him from believing God, by performing counterfeit miracles. (II Timothy 3:8)
Counterfeit apostles: Paul warned that Satan could display himself as an Angel of light through his human instruments. (II Corinthians 11:14) Many false teachers and prophets become hapless tools of Satan, but they deceive believers as if they were Angel of Light.
Speculators: There are other modern, postmodern, and liberal bible interpreters. They speculate, imagine, impose ideas on text and misapply scripture to contexts. Their interpretation is beyond the meaning and spirit of Scriptural revelation.
Syncretistic theologians: There are a few who have high regard for various religions. They wish to follow Lord Jesus Christ and also do not want to cut their umbilical cord with their old traditions. They try to justify unbiblical teachings by quoting one or two bible verses from here and there.
Hallucinating prophets: Sadly, there are a few who claim to hear audible voices or inner voices or experience trance. During such experiences, they claim to hear God or his angels.
Believers should flee from ‘dog whistle’ hearers/preachers.
Do I follow sound teaching of the Scripture?