I use startech "pro" adapters e.g. ICUSB2321F and a DB9F->DB9F null modem serial 'crossover' type cable.

Points to note are:

1) For Startech devices - don't bother with the CD in the kit - download the newest drivers from the the startech.com website. N.B. not all serial dongles work with Win 10.
2) The device may appear as COM3 or higher
3) Typical settings will be 9600 kilobaud ; 8 data bits; No-parity, 1 stop bit ( "8N1").

This setup has worked with HP and Microsoft laptops running Win 7 and Win 10 and talking to 568.2MM and G68ADV without problem.

Regards,
Graham

#1: StormAudioISPEliteMk1;DSP5K2/5K2HC/D33x6/D2500;RoonRock/Tidal
RegaPlanar3/RB250/Carbon/NADPP2;SonyTCK850es;CaCXUHD;CaAzure651T;GoogleTV; FireTV4KMax;AppleTV4k;Virgin360/Philips 65OLED950;SonosArc
#2: 562v2;DSP5K;FireTV;SonyBDPS3700;CAAzure640T
Spare: 568.2mm (faulty);596s;DSP5000C;M60C;Explorer2;G68ADV;