Yes - I found the same thing, and was totally thrown by the logistics of trying to hold 2 bits of kit in place, and switch on the machine, and turn it up as I'm able to, AND do the compression/massage I needed to do to get all the milk out!

But I persisted - I found that as long as I sit in a chair with a footrest, I can put my foot or feet on the closest edge of the chair and therefore rest (actually, it's more like 'wedge') the bottom of the collection container on the top of my thigh/s (it helps if there are creases in your trousers to create a ridge to stop it slipping). Then I wriggle one hand over so that the inside of the bend of the elbow supports the top of the flange on that side, keeping the flange in contact by squeezing it in to my chest, and I use that hand to hold the flange on the opposite side. That frees up one hand for adjusting the machine or doing compression/massage. (Or playing Words With Friends ) I always massage the side being held by hand, not by elbow, as it's too easy to accidentally break the suction on the elbow side because the weird position on the elbow side means the contact and suction isn't even all the way round.

I have also found that, although I don't get more milk from double pumping, I get more milk without having to do nearly as much compression/massage. I find that double pumping gets as much milk as it can in about 6-7 minutes (where with single, it stopped after 1-2 minutes and then I needed to start compressing) and now I only compress for the last minute or two, and only get a tiny bit more milk from doing that. So now, I usually just do the elbow hold long enough to adjust the suction up to full (it takes me a minute or two to tolerate it, especially on my still-ulcerated right nipple) and then just hold each side in one hand for the first 7-8 minutes. That was I can sit up in a straighter position, which of course is better for my back, and means i don't have the weird flange-digging-in-to-the-underside-of-my-boob thing going on.

For me, it was worth persisting with double pumping, even though it hasn't unfortunately improved my supply at all. Even though it was only 10 minutes each side, cutting it by half by double pumping made a huge difference to how I felt about pumping, and I don't resent it nearly as much now. Being able to relax and not squeeze and poke and watch the milk coming out the whole time means my neck isn't so stiff from looking down all the time, and I can actually relax, watch TV, close my eyes and meditate, play a phone game or read a book at the same time. And of course being able to relax is a key for getting letdowns, which I think is why I get more out without all the compressions now!

I really hope it helps, and that you get all those benefits AND a boost to your supply!