Freeswitch/Fusion stop/resume record on the fly

Most common solution to pause/resume recording on Freeswitch is use stop_record_session and after - record_session along with RECORD_APPEND=true.
What is bad with this solution.
1. Only WAV is supported
2. Seems it's broken for now (1.6.18)
Other option to use is
uuid_record mask/unmask

For FusionPBX it will looks like
action - bind_digit_action - local,*1,api:uuid_record,${uuid} mask ${recordings_dir}/${domain_name}/archive/${strftime(%Y)}/${strftime(%b)}/${strftime(%d)}/${uuid}.${record_ext},${bind_target}

action - bind_digit_action - local,*2,api:uuid_record,${uuid} unmask ${recordings_dir}/${domain_name}/archive/${strftime(%Y)}/${strftime(%b)}/${strftime(%d)}/${uuid}.${record_ext},${bind_target}

So, you may press *1 to stop recording and *2 to resume it. Bad in this solution - you will have pauses in conversation while record is masked.