Yup. I don't know if it happened on 4.2.2 or not, I got the phone, upgraded as soon as I opened it to 4.4.2 (v7 Sprint) and rooted, changed the audio to Dolby installed the viper audio app and made a call. It echoed bad. So, because I like to flash things (hubba hubba) I decided to flash back to stock 4.2.2, but like a retarded honey badger who doesn't give a ...., I forgot to test the call quality before I accepted the update back to 4.4.2.
So, most definitely happens on my phone, both with WiFi calling on or normal calling mode while using KK.