Hey all,
I have been successfully flashed a bunch of Sonoff Basic about 6 months ago with Tasmota 5.14 using FTDI devices. Last month, I was thinking to flash some new Tasmota firmware for Sonoff Basic and Sonoff S31 using the same FTDI. However, my computer just can’t communicate with Sonoff. I tried both PaltformIO and ESPEasy. I tried four different laptops (2 MAC and 2 PC). But none of those worked.I googled quite a bit and bought the Arduino board (suppose to provide enough power to flash). The symptom is the same - I just can’t flash anything. It has been very frustrated. Wondering anyone who can successfully flashed Tasmota live in the bay area so I can pay a local visit to get some help. Really appreciate it if anyone can help out. I can offer a free lunch if that helps 
Thanks,
Sean