DEFINES+="MUMBLE_VERSION=${TRAVIS_COMMIT:0:7}"
DEFINES+="MUMBLE_VERSION=${TRAVIS_COMMIT:0:7}"

Try to make the string shorter
Lartza/mumble,Lartza/mumble,Lartza/mumble,Lartza/mumble,Lartza/mumble,Lartza/mumble,Lartza/mumble,Lartza/mumble