Buzzing sound

I have a Manafont Ultrafire XML-T6 drop-in in a Skyray S-R5 host, and in the low/med modes there is a buzzing sound when I put the torch to my ear. (the high mode does not have the buzzing sound)

Is this normal?

Also, sometimes when I press the switch on the torch, it does not turn on and I have to press it mulitple times to get it to turn on. Otherwise it works fine.

Sorry for my noob questions, I'm kinda new to this stuff.

Welcome to BLF LegendZenify!

It is good to have you here.

It's the driver circuit. In some modes it physically vibrates at the PWM frequency. Hence the buzzing. Some people find it incredibly annoying, others like me don't notice it at all or aren't bothered by it. It isn't anything to worry about.

I'd try tightening up the switch retaining ring - and see if that fixes it.

Aloha and welcome to BLF LegendZenify!

I have a Yezl Z1 XM-L that does this. If the tail cap is not firmly tightened, in some positions it will hum and buzz quite loudly. A very slight turn of the tail cap will vary the pitch and volume noticeably.

The Trustfire F20 I just got today did that, and flickered some. I opened it and cleaned off the area where the + terminal of the battery makes contact, with rubbing alcohol. That seemed to fix the buzz and the flicker...for now anyways.

Thanks for the replies, though I still don't understand terms like a 'switch retaining ring' - could you elaborate?

Also, there is another problem - the switch seems abit iffy, the light does not turn on sometimes when I press the switch.

Another thing - could someone enlighten me on how to change the lens on the Skyray S-R5?

On another note, thanks for the welcome.

Remove the tail cap and look inside. If you look closely you will notice that the guts of the tail cap are screwed in. I'm not familiar with the light you have, but you may notice a couple small holes on opposite sides, close to the threads. You would use a pair of small needlenose pliers or even tweezers to grip these holes and unscrew the guts of the tail cap. Sometimes the holes are not there and instead you may see a couple of tabs of very thin metal, almost like foil, gripping the threads. I don't yet know how to remove this latter type, so perhaps someone else can enlighten us.

Edit: The third photo in this thread shows a retainer ring removed from the tailcap.

Welcome to BLF LengendZenify! I hope you enjoy it here.