Need help diagnosing dreamcast issue

[cartwrite]

long story short:
-got new (to me) dreamcast
-should play CD-Rs
-back ups wouldn't work, but Utopia loads fine
-re-made copies of back ups many ways--no issues making it wrong

So I have the list of what could be wrong:
-poor CD-R quality--unlikely, they're TDK and the utipia disc works
-issues with my hardware/software for burning--unlikely, others were successful with a mac (I tried on mac and windows on the mac)
-worn out dreamcast laser--I didn't think this was the case because Utopia works

Well I decided to adjust the laser, and was excited to see the dreamcast playing a CD-R. Now the issue. It will play a CD-R, but to play it again, I have to re-adjust the potentiometer of the laser. So If I'm playing a back up and turn the console off or switch games I have to re-tune the potentiometer or it will not read the back-ups, but will still read Utopia. Also, I noticed that no matter what I did to the potentiometer whether it was tightened down or loosened up all the way, the dreamcast would still read GD-ROMs and Utopia, but not back ups on the same exact cd type burned the same way. I know the back ups work and the cd quality must be ok. Since I want to play my dreamcast with the case properly secured on it, what options do I have? And does anyone where I could (if I had to) buy a new laser or a new GD-ROM? (my quick search yielded nothing of use)