Arduino IDE and ESP32

I am using the Arduino 1.8.4 trying to send audio type array data to the I2S port and out the inbuilt DAC. I took and example from the espressif ESP-IDF examples for I2S.
Below is it modified as I "think" to suit the Arduino...but cannot get it to work. It compiles and runs no errors but no sound out the DAC.

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//square wave as a 20 point array

const uint8_t p20[20] = {180,180,180,180,180,180,180,180,180,180,20,20,20,20,20,20,20,20,20,20};
// I2S_BITS_PER_SAMPLE_16BIT,.....?????

#include "driver/i2s.h"
#include "freertos/queue.h"
char data = 50;

int i2s_num = I2S_NUM_0; // i2s port number

i2s_config_t i2s_config = {
.mode = i2s_mode_t (I2S_MODE_MASTER | I2S_MODE_TX | I2S_MODE_DAC_BUILT_IN),
.sample_rate = 8000,
.bits_per_sample = I2S_BITS_PER_SAMPLE_16BIT, // tells me bits not set if 8 bits ???
.channel_format = I2S_CHANNEL_FMT_RIGHT_LEFT,
.communication_format = I2S_COMM_FORMAT_I2S_MSB,
.intr_alloc_flags = ESP_INTR_FLAG_LEVEL1,
.dma_buf_count = 8,
.dma_buf_len = 64
};

i2s_pin_config_t pin_config = {
.bck_io_num = 14, //this is BCK pin .....pins for Firebeetle esp32 I2S pins
.ws_io_num = 17, // this is LRCK pin
.data_out_num = 4, // this is DATA output pin
.data_in_num = -1 //Not used
};

void setup()
{
Serial.begin(115200);
//delay(2000);
Serial.print("Initializing setup......");

//initialize i2s with configurations above
i2s_driver_install(I2S_NUM_0, &i2s_config, NULL, NULL);

i2s_set_pin ((i2s_port_t)i2s_num, NULL); // null for dac

i2s_set_dac_mode(I2S_DAC_CHANNEL_BOTH_EN);

//set sample rates of i2s to sample rate

i2s_set_sample_rates(I2S_NUM_0, 8000);

// i2s_driver_uninstall(I2S_NUM_0); //stop & destroy i2s driver
Serial.println("done!setup");

}

void loop()
{

i2s_push_sample(I2S_NUM_0, &data,1000);

data++;
if (data > 120) data = 50 ;
// just trying to send this data in loop to see if it works rather than the array above??? not work.??
}

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Below this is what I get on the monitor screen

ets Jun 8 2016 00:22:57

rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
ets Jun 8 2016 00:22:57

rst:0x10 (RTCWDT_RTC_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0x00
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:1
load:0x3fff0008,len:8
load:0x3fff0010,len:1760
load:0x40078000,len:6668
load:0x40080000,len:252
entry 0x40080034
Initializing setup......done!setup

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Would be grateful for some help please.
I have the firebeetle ESP32 with the WROOM module on board
I am using windows XP.