(xQueueGenericReceive)- assert failed!

Why simple button check will fail ??

pinMode(16, 'input_pulldown');
pinMode(17, 'input_pulldown');

setWatch(function(e) {
  console.log("Button 17 pressed");
}, 17, { repeat: true, edge: 'falling', debounce: 50 });

setWatch(function(e) {
  console.log("Button 16 pressed");
}, 16, { repeat: true, edge: 'falling', debounce: 50 });

And result is:

>ets Jun  8 2016 00:22:57
rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
flash read err, 1000
ets_main.c 371
ets Jun  8 2016 00:22:57
rst:0x10 (RTCWDT_RTC_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:2
load:0x3fff0018,len:4
load:0x3fff001c,len:2364
load:0x40078000,len:0
load:0x40078000,len:10880
entry 0x40078c4c
WARNING: setsockopt(SO_REUSPORT) failed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
Button 17 pressed
>/mnt/c/Users/rhys/esp32/EspruinoBuildTools/esp32/build/esp-idf/components/freertos/./queue.c:1442 (xQueueGenericReceive)- assert failed!
abort() was called at PC 0x4008a168 on core 0
Backtrace: 0x4008c743:0x3ffdbfb0 0x4008c76f:0x3ffdbfd0 0x4008a168:0x3ffdbff0 0x40107bda:0x3ffdc030 0x40109f04:0x3ffdc050 0x4010a253:0x3ffdc070 0x4010b536:0x3ffdc0c0 0x40136075:0x3ffdc140 0x401af1b1:0x3ffdc170 0x4015b2bb:0x3ffdc190 0x4015b51c:0x3ffdc1b0 0x4012e39c:0x3ffdc210 0x4012999f:0x3ffdc230 0x40129b05:0x3ffdc2a0 0x4014a845:0x3ffdc2c0
Rebooting...
ets Jun  8 2016 00:22:57
rst:0xc (SW_CPU_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:2
load:0x3fff0018,len:4
load:0x3fff001c,len:2364
load:0x40078000,len:0
load:0x40078000,len:10880
entry 0x40078c4c
Button 17 pressed
WARNING: setsockopt(SO_REUSPORT) failed

What could cause this :( ?
Other ways is to use setInterval to check digitalRead pin state... but this is not the right way :(