Fix some ESP32 compile warnings

Author: pschatzmann

src/AudioI2S/I2SESP32.h

@@ -338,9 +338,14 @@ class I2SBase {
 #if defined(USE_I2S_ANALOG) 
           mode = (i2s_mode_t) (cfg.rx_tx_mode ? I2S_MODE_DAC_BUILT_IN : I2S_MODE_ADC_BUILT_IN);
 #else    
-          LOGE("Not supported");
+          LOGE("mode not supported");
 #endif
           break;
+
+        default:
+          LOGW("signal_type undefined");
+          mode = (i2s_mode_t) (I2S_MODE_MASTER | I2S_MODE_TX);
+          break;
       }
       return mode;
     }

src/AudioTools/AudioStreams.h

@@ -274,7 +274,7 @@ class MemoryStream : public AudioStream {
       buffer_size = size;
       switch(memory_type){
   #ifdef ESP32
-        PS_RAM:
+        case PS_RAM:
           buffer = (buffer==nullptr) ? (uint8_t*)ps_calloc(size,1) : (uint8_t*)ps_realloc(buffer, size);
           break;
   #endif

src/AudioTools/AudioStreamsConverter.h

@@ -120,12 +120,16 @@ class ChannelFormatConverterStream : public AudioStreamX {
             switch(bits_per_sample){
               case 8:
                  static_cast<ChannelFormatConverterStreamT<int8_t>*>(converter)->setAudioInfo(cfg);
+                 break;
               case 16:
                  static_cast<ChannelFormatConverterStreamT<int16_t>*>(converter)->setAudioInfo(cfg);
+                 break;
               case 24:
                  static_cast<ChannelFormatConverterStreamT<int24_t>*>(converter)->setAudioInfo(cfg);
+                 break;
               case 32:
                  static_cast<ChannelFormatConverterStreamT<int32_t>*>(converter)->setAudioInfo(cfg);
+                 break;
             }
         }