Laptop PSUs - bit OT - sorry

Posting here cos this is where all the clevers hang out!!

Was just working on mates laptop this week and he got a little 'tingle' off it.
Upon investigation, there seemed to be about 50v between chassis and mains earth.
Ah I thought - it's duff!(and dangerous?)
Investigated further and on a couple of others (including a proper Sony one as opposed to Maplin ones)and found anything up to 120v AC from either leg of the DC connector to earth (even the PSU with an IEC 'kettle connector' didn't have the earth pin connected to anything) and all measurements everywhere were up in the Megohms.
Took my life in my hands (silly me perhaps as no isolating transformer in use!) and measured with 'me' across from PSU to earth.
I felt nothing and the volts went down to about 50v or less.
I haven't got the 'scope out yet to see what is present frequencywise

Is this a feature of these cheap Chinese PSUs that there is a massive leakage from the inverter to the o/p?

Should one ignore it?

I guess the external PSUs used in some hi-fi and satellite receivers may be the same.

I seem to recollect reading somewhere (PC Pro) that this is common.

Any ideas?

Mike

(who never could mend BBC 25dB high level video send amps and so left them on the 'faulty' shelf so someone else might - or they got thrown out)

.

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