sega saturn Trouble with booting games Sega saturn

[RetroBish15]

Hi. I have 2 sega saturns that I got off ebay. Both were listed as non working/not tested. saturn A had a bad laser and saturn B had this other issue. Saturn B would read the games no problem and then load them (I tested it with a real copy of all star hockey) the sega license screen would show, then the SEGA sports logo would show, then it would stay black and the disk keeps spinning. I then took the laser (whole assembly) out from saturn B and put it into saturn A and it worked perfectly. I even flashed an action replay cart with pseudo saturn and saturn A was able to play all the burned games I threw at it (North american and international). When I put all the lasers back in their homes and tried to boot some of the burned games I had on the Saturn B with the pseudo saturn cart in it, only 2/12 games fully booted. Policenauts and Galactic Attack. I really dont think it is a laser issue because I tested out the laser and it works fine and then I bought two new lasers for them and installed them. Saturn A works flawlessly with the new laser but saturn B still does the same thing. it does read and boot games but stops after the sega licence screen. What else could be wrong with it. Maybe a crystal oscillator is not working, or is it in need of a recap? or maybe something else?
Just for reference saturn A is a VA SD and saturn B is VA7 both ntsc north american
Thank you for any help.