These tones like: dial tone, ringback tone, error tone, busy tone, dummy dial tone are set according to National standards from your own country.
Ask your local telephony provider about these timers.
And simultaneously you must program your LG PBX to the country code for your country. IN PGM100 your country code is set. If your country does not exist in the list, choose a country with similiar telephony networks as yours.
If you change the country code on an existing LG PBX you database is lost!
///doktor