Hi Mike, Welcome to the Discovery family. We also have a Discovery LXE and sometimes have low water pressure in the shower depending on campground pressure. One thing I did was crank up my adjustable water regulator or remove it. Check your water filter. Dirty filters can restrict your water flow. Check your hose screens, they can catch dirt and restrict water flow. If you are using the on board water hose on the reel, try hooking up a hose to the inlet in the water bay. If that improves your flow maybe you have a restriction in your hose reel or a kink. Also make sure your water bay shower faucets are turned off. Ours seems to have gotten better over time. Not sure what more to suggest.
Also If you are not a member of DOAI (Discovery Owners Association) I would like to invite you to take a look and join the club. DOAI forum is second to none. Only Discovery owners. Take a look at
Discoveryowners.com
Jim Pinkerton 2018 Discovery LXE 40D