My DreamCast is making sounds like it will die any day now, I should probably get in on this dreampi stuff and play some PSO before it grabs it's last chaos emerald 
Sounds like a brand new Dreamcast tbh
I've been saying this for at least 8 years, so yeah
the drive? yeah, that gets louder and louder, actually all drives do this but usually other noises overpower it but the GD-ROM drives are loud to begin with because of the way they spin the discs (not exactly continuously) ... my slim PS2 now has an audible drive since the machine emits essentially no other sounds and it's just worn over the years, works fine though
also, if you're using any CD burned games, there's a new set of rips that don't tax the drive like the prior two sets did...DC games are supposed to be burned backwards and in a specific manner; because they read CD's with a simple pre-boot statement a lot of the older rips, especially ones that were remastered to fit on CDs, aren't setup to burn properly
if your Dreamcast doesn't ever boot or is hit and miss about booting, the power supply pins are often actually the only problem...most things on the DC that need minor adjustment aren't really huge problems because of how easy it is to get into the case and how everything inside is stacked and also easily disassembled, that's actually another reason the drive is so loud comparatively, it's right on top of the fan so you don't hear that unless you're under it for some odd reason you sick freak (also the DC uses really thin plastic)