Finding a reliable "HSP56" (Host Signal Processing) sound card driver is a common challenge for those maintaining legacy hardware, as these were often budget-friendly components integrated into older motherboards or modems.
Finding official drivers for such old hardware requires using reputable driver archives: hsp56 sound card driver link
The Internet Archive has preserved several OEM recovery CDs containing HSP56 drivers. HSP56 Sound Card — Driver Resources Quick download links
You can find various versions of the HSP56 driver on these driver database sites: PCTel HSP56 MicroModem Drivers HSP56 drivers are legacy Windows drivers for the