PPG wave 2.2 vs 2.3 are there any differences?

I used to have a PPG wave 2.3 and I also got a 2.2 later on. Then I had to decide, which to keep and I compered them to each other. I prefered the 2.2. In this video you can hear some dfferences. The 2.3 sounds in many patches weaker and the panorama settings of the voices behaves sometimes strange. I suppose that the unit has some slightly issues, althought it got a full service and overhaul. The 2.2 didn't get any service at all. Also the envelopes seem to behave slowlier on the 2.3. When regariding the specs, the transient sounds in the PPG Wave 2.3 played with 12 bit or with non-linearly scaled 8 bit. The 2.2 played with 8 bit. Both PPGs used the same DA converters. Both used the same filter SSM 2044. In both PPG i had the latest OS 8.3 developed by Hermann Seibt. So I wonder why there are sound differences. My thesis is, that the 2.2 should not sound different from the 2.3. In this video it does. Now I only have the 2.2 in my studio, I sold both, the 2.3 and also the EVU, which you can see in this video.