Hiss and crackling noises

[PaulieDee]

Good morning. I just received a brand new PRS MT 15 this week. I have noticed a hiss and crackling noise coming from my 2x12 cabinet when the amp is in standby. I haven't had a real amp in years and wondered if this was normal. I've tried different speaker cable including a brand new one and also isolated the power trying it plugged in different areas of the house but it's still doing it. Anyone know if this a known issue.?

Thanks
PaulieDee

 

[Maertl513]

Nobody knows the actual electrical situation in your flat. It deemed being an antenna/shielding issue. A "new one" speaker cable doesn't give a hint, if they are of good quality, do they?
A friend of mine has a MT-15. I confirm a noticeable hum in stand-by.

 

[ViperDoc]

New amps will hiss and crack for a while as they break in. Not to worry. Also, standby switches place stress on your tubes when kicked back in via extreme inrush current. I suggest never using a standby switch. If you have to silence the amp, turn your guitar volume down.