LC-1 developer precipitated crystals

Last week I made up some LC-1 developer and arrived today to find that it had precipitated out a large number of long crystals. I did make the developer double strength, as I had hoped it would cut my long developing time for lith film (which it did). I am assuming that it was the sodium sulphite which caused the crystals? Doubling the sodium sulphite meant adding 120 grams to 1 litre of solution A. I'm wondering if I need to add that much sodium sulphite, perhaps you only need a certain percentage, assuming that it's not actually an active part of the developer? I have strained the developer but haven't used it yet.
So my question are:
-were the crystals from an over concentration of sodium sulphite?
-do I need to use double the amount of sodium sulphite in a double strength developer?
thanks
david