Sony SCD-C 555ES

Just purchased this used, set it up and am disappointed in the performance, both redbook and SACD. Compared to my Cal Audio CL 10 - it has little soundstage, no depth or width, and seems quite bright. I expected this on redbook performance, but it doesn't change much on SACD.
I'm going to assume that the previous owner slimply didn't play it enough to break it in.
If I decide to allow it to run for another 100-150 hours do I have to turn on all my equipment or can I just leave the Sony on alone. Does break-in require your whole sysytem to be on?