Faint prints from my Epson 2000P

My repair shop just replaced the printer head on my Epson 2000P (because it
was printing small red lines in all my prints), but now, the prints are only
about half as dark as the actual image. Some web sites suggest it's likely
a printer driver issue. Before the repair, I installed what I understood
was a newer driver for the 2000P to use with my XP Pro.

When I try to re-install the original driver that came with my printer 18
months ago, Microsoft says it's not necessarily compatible with XP and warns
me not to install it. I believe the "XP compatible" driver from the Epson
site is installed, but that's the one that may be making it print light.
Also, I haven't installed Service Pack 2, so I don't think that's the
problem. I'd appreciate any suggestions! Thanks, Stuart