Hi Rob Jones, which Volume apps you downloaded, I can't find the apps.
I tried Volume Control by Truapps, RevsoDev, Volume Control+ by Coffeebreak Apps etc. but all don't work.
Whenever I switch off the phone and switch on again, the In-Call volume is back to high setting.
My phone is now updated to 4.2.2 and it's still the same.
All other volume setting such as ringtones, notifications, media, alarm is OK, remains at the desired settings.