Something doesn’t sound right. That Audiolab should have lower jitter for the spdif than the Oppo 93. I have an Oppo 93 and used it as a transport for some time. It never sounded quite right to me, harshness in the highs, and after playing around with some different transports found it was the culprit. So, I ended purchasing a dedicated transport.
Are you saying you prefer the Oppo 93 as a CD player (using the internal DAC) compared to the Audiolab transport to another DAC? Or, the Oppo 93 and the Audiolab are both being used as transports only, and both are going to an external DAC?
What connection are you using? Spdif? What kind of cable?
Perhaps you are hearing a higher resolution signal from the Audiolab and don’t prefer that sound? You might trying a different spdif cable. They affect the overall sound pretty significantly.