Mp40s are very quiet.

If its loud it's one of these 2 things:

Dry and wet side not lined up perfectly.

And/or

Dry side magnet is rubbing on the rubber spacer. Also the rubber spacer has 3 nipples that need to go into the holes but sometimes they miss the holes and bend and rub against the dry side magnet.

Personally mine are 10's... they have been checked(lined up... no spacers...) ... it is a hardware problem. The good one is very silent.

you're not using the spacer on the dry side? so your magnet is directly exposed to the glass?

The 10's don't have the pin style spacer, they just clamp on or if the glass is very thin below 3/16" i believe then there is a spacer to put in. The 40's have the pin spacer and the 60's have different spacer that slip on.

ohhh ok gotcha. well i found out why my mp40s were making noise. the pins on the spacers bent and were rubbing against the magnet. now they're perfectly silent

Are they quiet at 100% though? Mine are acceptable at lower power, but irritating at full.

They are aligned correctly, using the correct spacer setting, etc.

When you say your pins were bent, is this inside of the unit?

I've bought new bearings to try. I just need to get my hands on a bearing puller.

Yes mine are a 100% the pins are on the spacer on the dry side

Uh oh, now I'm worried how mine will sound lol.

Is the pulsing mode (which from the sounds of it is the most audible) used simply for wavemaking?

Short pulse makes waves. Long pulse makes a swaying motion.

It's an LCD tv. Does'nt do this on my main TV just the TVs in the bedrooms. Bell Xpressvu receiver. Once again, I know it's the MP40s 'cause when the power is turned off to them the lines disapear. I've contacted Ecotech and they say that it's not due to their product. I'm used to it now and it does'nt bother me. Just letting others know.