My amp (Bogner Atma) makes these noises whenever it's switched on/off. The little research I did leass me to believe it's a tube issue (specifically power tubes). Is this the most likely
Bogner Atma Head – Thomann United States
Bogner Atma - 18 Watt Tube Guitar Head - Ecstasy Style
Bogner Atma Head – Thomann United States
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Bogner Atma - 18 Watt Tube Guitar Head - Ecstasy Style
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Bogner Atma - 18 Watt Tube Guitar Head - Ecstasy Style
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Bogner Atma Head – Thomann United States
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Bogner Atma Head – Thomann United States
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Bogner Atma Head – Thomann United States
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Bogner Atma - 18 Watt Tube Guitar Head - Ecstasy Style
