Surf soho hissing at me

i was in my tech closet today and I heard a hissing noise, it was like “hiss hiss hiss hiss”. it sounded electric so I didn’t think it was an animal. then I heard it again and followed the sound to my surf soho. is this noise normal?

Animal sounds of any kind from a Peplink device would always be classed as unusual…


I have used the Surf soho now for three years, never heard it hissing.

If it’s electrical, and / or electronics, you would smell it.

I would look around more…may be a snake in there.

thanks for replies, guys. your routers don’t make any noise at all? I just went in to listen some more, and mine definitely makes noise, but I guess it’s more faint than I thought it was. it is definitely coming from the router and it’s electrical noise. it’s intermittent but I can hear it any time I go to closet and listen. should I contact pepwave support?

Well, if its hissing I’d either contact my local wildlife control officer or tech support. Depends on how loud and threatening it sounds, I guess! :rofl:

I found this on the google:


Please open a ticket for support team to check.

  • Make sure you are using the default shipped power adapter
  • Possible please provide a video clips for the Surf Soho that include the hissing sound.
1 Like

I just sent a support ticket, I’ll try to get a recording as well.

I have had complaints about very faint nosies from the AP ONE Enterprise in accommodation areas. We just moved the APs out of audible range.

I’ve just began setting up my Surf Soho mk3 and mine is also making hissing (high pitched almost buzzing) noises. They appear to sync up with the devices CPU usage.

The unit itself was a 2nd hand ebay item so unfortunately no recourse in my case, but can I just confirm the PSU brick it came with is correct?

Brand: APD
Input:100 - 240v (0.65A max)
Output: 12v @ 2A

It’s a tad annoying as in my case the router sits in my living room, and I can hear it from my sofa so I think I’m going to have to go back to my ISP supplied router until I can get this resolved somehow or get a replacement unit.

The spec for the power supply appears to be fine. Is the noise coming from the SOHO or the wall wart?

It’s coming from the SOHO itself, and the amplitude seems to relate to how hard the CPU is working. Could be coil whine I suppose.

coil whine?

The coil in a relay and/or it’s contacts of the relay making a Noise, or a whine sound.

Wikipedia is your friend (and you donated?):