You might have to turn up your volume to hear this. At about 24 seconds you will see the red light dim a little and if your volume is up you can hear a weird noise. This is when I turn on my hotbed. The red light flickers and the light on my bed will turn on for a second and back on. The bed gets hot as well but I’m not sure if this is a problem.
chad this look like a azteeg 5x ? if it is your heat sink goes underneat the pcb
Yes it is a Azteeg x5 mini, you mean the black long one for the stepper drivers
Yes it goes under the pcb
My heatbed wire creates a perceptible hum when it heating the bed - it has never caused a problem for me. I imagine it’s not dissimilar to the hum created by overhead power lines. I do know that you want to make sure the connections into the heatbed screw terminals are good every so often - I may have melted one by not checking such things regularly.