modem isn’t connect after flash storm

I have 56Kbps modem WebExcel MD3228. On the next day after flash fallen down to post service modem isn’t communicate correct. it changes his “melody”. i tryed modem at different phone lines-the same (can’t establish the connection). sometimes when connecting at other ISP modem leaves flat tone at end and i must hung-up manualy.
Could anyone tell what can i replace on my modem to repaire it, or whole chip (or both two)is broken?