Hi every one, I have a Siemens power supply 5Amp 24 volt output and 120volts , 220 volts input. The problem is I think in transformer. It creates voice like ticking. Output voltage keeps 24 volts for about a minute and after fluctuation begins (22.x-23.x). I tried to change capacitors but the same problem. I could not find any manual or drawinds. Can anybody suggest something, may be some additional information would required , in that case I will write, thanks in advance