Starsound d2500 power supply problem

Hi guys im currently busy doing a power supply repair on a starsound d2500 2 channel amp i replaced the tl494 ic took out buffer transistor and fitted bd 139 and bd 140. Without power supply fets the drive looks good nice and square but when i fit fets it changes drasticly I'll post pics of the drive later. It has in 47ohm resistors on the gates and 220ohm pull down resistors I also removed the rectifiers to isolate power supply from output section the power supply fets are Irfz44n
 
This is the drain of power supply fets wave
 

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