I've been currently very sick so haven't been able to get out fishing but I was told the bass are very lethargic and hard to catch. The water temp is 46 degrees.

What are some good techniques to catch them on lipless or lipped crankbaits? What retrieves and speeds?

Thanks for the help!

cold weather I use a Shad Rap for the tighter wobble.

When the water is that cold, softly yo-yo-ing a rattle bait across the bottom is a good way to put some in the boat.  A Rapala Shad Rap or another tight wiggle crankbait retrieved at medium speed just above the bottom also works well.  Only the fish can tell you how fast a retrieve is best.  It depends somewhat on water clarity because you never want the bass to get too good a look at a crankbait, but in cold water I'd start out fairly slow and experiment from there.   

I like to use the Rapala DT3 Flat in these conditions.