So sad to hear you miss Metso!!! I'm prety sure my little division will be up next for sale net, since we are also have a new idea about making money, not spending it uselessly, but don't get me started....
I can't see how making the line bigger would make the problem better, I would think it would just get worse. I can't hear mine at all. Maybe you solenoid needs a cleaning? Just a guess.
You could also install a secondary solenoid, electric on a timer, so it is only on for 1 hour a day, or enough time to make noise and fill your container.
Lee