Solving the “pop” problem on my B&W ASW608 subwoofer

I have finally managed to get to the bottom of the "pop" problem on my Bowers and Wilkins ASW608 subwoofer. I understand the problem affects the ASW610 subwoofer as well.

The solution is to set the EQ on your amp to reduce frequencies 30Hz and below, which the sub can’t reproduce anyway.

The problem is sometimes you hear a loud “pop” during playback.

The internet suggests returning it, but the internet also suggests the new one you get may have the same problem. Given I understand it’s been a problem since at least 2009, and it’s 2025 now, I’m not thinking this is a newly-discovered problem they’ll soon get around to fixing.

I managed to ascertain the following facts:

• The pop happens repeatedly at particular times on particular films. When watching the film “Deadpool & Wolverine”, it happens at 37:35 exactly, for example. This means it isn’t random e.g. a loose connection.
• If I turn the volume down on the sub, at some point it stops happening. It’s binary: either it happens very loudly, or not at all. Given the volume on the sub affects it, it’s not a problem of the amplifier or the source outputting the pop sound and the subwoofer faithfully reproducing it. The problem is with the sub, not the amp or source.
• The sub has various EQ modes (A, B and C). The default is A. Using B or C reduces the chance of the pop but not completely, and also the bass is pretty weak then, to the extent even if you put your ear right by the speaker you can hardly hear anything below 50Hz. So that isn’t really a solution.
• The subwoofer has a light at the back. When the pop happens, the light turns orange for a few seconds. The sub manual says green=on, red=off, but does not mention orange at all. This sort of implies the sub broken or at least not working as intended.
• The subwoofer has an inbuilt amplifier. This is manufactured by a third party and is a 200W amplifier from ICEpower aka B&O (source).
• The ICEpower200ASC manual says it has an output for the red light, and for the green light, and that in “protection mode” it outputs a signal on both. Red and green combine to make orange, so I assume that’s what I’m seeing.
• There are various reasons the amp manual lists for “protection mode” to be engaged. The most plausible seems to be that the power limit is exceeded. I am not listening at very high volumes so that is surprising.
• By pure luck I was testing a sine wave generator on my PC and I found out that the pop happened when I went down to about 31Hz. This makes some sense, as lower frequencies require more power to reproduce.

The solution I came up with was the alter the EQ on my AV receiver to pretty much silence frequencies of 31Hz and below.

The subwoofer specs claim it can only go down to 32Hz at −3dB, and my experience is it can reproduce sounds down to about 35Hz, so reducing sounds below 31Hz is not removing anything you can hear.

Another solution might just be to get a different subwoofer, but it took a long time to find one which had all the features I was looking for and at a size I was looking for and at a price I was willing to pay and which doesn’t look terrible, so I wanted to try and keep it if possible.

I hope this helps you if you have the same problem.