That's why we have NO part between ES9218p output and 3.5/2.5 audio jack. We want to have the pure output from ES9218p go to the audio jack directly.
Please note that some application products have switching IC between them, which works as a resistance even at ON state.
Every semiconductor switch IC has some amount of resistance at ON state, which is called Rds-ON resistance.
Anyway, we always keep that in our mind when designing 5k.