fix low PI RDS callsign decoding #1198

Job	Run time
build_debian_bullseye	3m 3s
build_debian_buster	2m 55s
build_debian_bookworm	3m 35s
build_macos	8m 39s
build_windows	12m 28s
build_android	12m 31s
build_raspios_bullseye_armhf	8m 38s
build_debian_sid	3m 57s
build_ubuntu_focal	4m 25s
build_ubuntu_jammy	2m 58s
build_ubuntu_mantic	3m 33s
check_formatting	12s
check_spelling	20s
create_full_archive	9s
update_nightly_release	7s
	1h 7m 30s

Provide feedback