Replying to Any Way To "Unpack" Liners?

My boots fits amazingly for the last few seasons, but this year I'm noticing they're not quite as snug and I'm getting some bad tendonitis in my achilles because of it. I've been cranking the tightness up as much as I can, but it feels to me like the liners are just packed out. Is there any way to "unpack" liners and get them feeling the way they used to? Or am I better off throwing in some footbeds/getting new liners?