The difference in volume between CD and phono is normal.
The issue is the digital standard was intentionally raised far over all the other source devices when the CD was introduced.
Normal phono, FM tuner and cassette were all at around 0.5 volts. The CD brought in a 2.0 volt standard. Which all other digital gear uses. But nearly all the old source devices still clingto the 0.5 volt average output.
So yes it sucks, but it is the way things are.
The issue is the digital standard was intentionally raised far over all the other source devices when the CD was introduced.
Normal phono, FM tuner and cassette were all at around 0.5 volts. The CD brought in a 2.0 volt standard. Which all other digital gear uses. But nearly all the old source devices still clingto the 0.5 volt average output.
So yes it sucks, but it is the way things are.