Buzzing noise, got shock by top of painted case

[cmipuci]

Hi, I Just finished building my crack tonight.
Checked voltage and resistance, all the numbers were good.

I then proceeded to plug the headphone in along with the DAC. Heard buzzing even at zero volume.
When I try to disconnect the headphone, I got shocked from the top of the case.
The panel did flip upward a little bit, but I didn't touch anything other than the panel itself.

I am not sure what is wrong. What else can go wrong when all the measurement were correct?

Thanks.

*I rechecked all my joint, how can I make sure the panel won't shock me without touching it myself?
** The buzzing noise stopped, turns out the noise was coming from a bad extension cable.
    Tried it with music and the amp sounds great.  But I am still afraid of getting shock by the panel when the amp is plugged in.
    Anyways to measure it without touching with my hand?

 

[Paul Birkeland]

You have an unsoldered or poorly soldered joint (maybe more than one).

Can you post some photos of your build?  We might be able to find it visually.  You can also reheat each joint and allow the solder to flow a bit more.

 

[cmipuci]

I will recheck all my joint.
Is there a way to know if the panel will shock me without touching it?
Kind of scared to touch the crack again without rubber gloves  :-\

 

[cmipuci]

Hi,

I got a small voltage, between .4-.6 mV consistently on all terminal that are supposed to be zero.
Is this within the margin of error, or something is wrong?

I got shocked by the top panel last night when I did my first listen, which had buzzing sound even at zero volume.
I proceeded to recheck all my solder joint, and redid the resistance and voltage test.
Is there anyway to test if the panel will shock without touching it with my hand, kind of scared to listen to the amp after last night's test.

Thanks for the input.

 

[fullheadofnothing]

Please do not make multiple threads about the same topic.

It is hard to speculate on what the problem is here — Paul's suggestion of posting images of your build is a definite place to start.

 

[cmipuci]

Last post/update for now

After reading the first reply, I redid all my joint and double check all the wiring.
Resistance and voltage checks were good.
I plugged the amp through an extension cord to test with headphone, I still heard loud buzzing.
I suspected that the extension cord is at fault, therefore I plugged the amp straight into the wall outlet.
With just headphone connected, all buzzing noise went away and the amp is dead silent.
So Buzzing was due to extension cord.

I am wondering if extension cord is the culprit for both the buzzing noise and the shocking, perhaps due to bad ground?

I didn't do anything more with the amp, because I am treating the top of the case as a possible shock hazard.
So is there anyways to test the top of the panel without touching it? 
I am too scared to do anything more with the amp currently, really wished I could listen to it instead of being fearful to it :'(

P.S. Is it normal to hear a crack/pop sound from the headphone when plugging in to the amp.

Thanks and sorry for double posting.
Just panic and impatient and didn't know what to do.

 

[Doc B]

Unplug the amp from the wall socket and remove the power cord from the amp. Remove the chassis panel from the base and turn it upside down. Set it back in the base. Plug the grounded power cord back into the IEC socket from underneath the base. Switch the power switch to on.

Use a clip lead to attach the black wire of your DVM to the ground tab of the IEC socket, labeled E. Set your meter to measure AC volts. Plug the power cord into the wall socket. THE AMP WILL BE LIVE. Touch the red test led to the chassis panel. You should see 0 volts or a very tiny voltage. Switch the meter to DC volts and test again, looking for 0 volts. Don't forget to unplug the power cord from the wall when you are finished!