Binding straps don't release easily - ideas?

I have a pair of Ride bindings on a board I got used recently.
The bindings don't release easily. Rather than just pulling on
the release lever, I frequently have to lift the tightening lever
a bit as I pull the release lever to get them to let go.
Sometimes, it takes several tries before they release. Does
anyone have suggestions for how to fix this? I'm thinking a
little silicone on the straps, but don't know if this would cause
problems.

Bob