diff --git a/platformio.ini b/platformio.ini
index 6895d014..93f4fdcd 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -2682,7 +2682,7 @@ build_flags = ${esp32_4MB_S_base.build_flags}
 [env:esp32_pico_4MB_M]
 extends = esp32_4MB_M_base
 board = pico32
-board_build.flash_mode = dout ;; (dout = dual out; more compatible than qio = quad i/o)
+board_build.flash_mode = dio ;; (dout = dual out; more compatible than qio = quad i/o)
 upload_speed = 256000 ;; or 115200 ;; or 460800 ; or 921600  (slower speeds are better when flashing without a soldered connection)
 
 build_flags = ${esp32_4MB_M_base.build_flags}