[Freeswitch-users] esl socket inbound + playback

Hello, I wrote simple C application, wich opens connection to esl - freeswitch and makes call (originate ... &park). So far so good. I get ESL_EVENT_CHANNEL_ORIGINATE, ESL_EVENT_CHANNEL_ANSWER and ESL_EVENT_CHANNEL_PARK. Then I wan't to play wav file - but playback command returns "-ERR invalid session id []". What is wrong? Specifying "originate ... &playback" is out of question.