Hi Ian,
Just select 'Last used settings' from the Presets dropdown. Or, better yet, set up preset(s) of your own. We don't do this automatically because if these filter settings include the hiss filter, you would get an annoying prompt (to define a noise sample) as soon as you opened the filter settings dialog. We need to prompt because ...
... hiss filtering works by subtracting the background noise from the music. It's not a perfect process of course - there is always some impact on the sound - but that's the basic idea. To do this, the hiss filter needs to know the amplitude and frequency spectrum of the noise in question. It's important (vital, actually) that this is as accurate as possible, so we prompt for it every time, but I suppose in the majority of cases that is overkill. You can record both sides of an album as a single file of course. That might save you a few mouseclicks.
If you get the noise sample wrong, it sounds terrible. You might like to try this, just for amusement. If you don't define one at all, or select a silent section before the needle drop, say, there is nothing to subtract so no hiss gets removed. Some programs try to guess or make a suggestion, but the effects are so bad (or, "huh! it doesn't work") if it gets it wrong that we don't like to do that. It's much better that people master the process for themselves.