more i2s/bt drain buffer size tweaks

src/audio/audio_fsm.cpp

@@ -199,11 +199,11 @@ void Uninitialised::react(const system_fsm::BootComplete& ev) {
   sServices = ev.services;
 
   constexpr size_t kDrainBufferSize =
-      drivers::kI2SBufferLengthFrames * sizeof(sample::Sample) * 8;
+      drivers::kI2SBufferLengthFrames * sizeof(sample::Sample) * 2 * 8;
   ESP_LOGI(kTag, "allocating drain buffer, size %u KiB",
            kDrainBufferSize / 1024);
   StreamBufferHandle_t stream = xStreamBufferCreateWithCaps(
-      kDrainBufferSize, sizeof(sample::Sample) * 2, MALLOC_CAP_DMA);
+      kDrainBufferSize, sizeof(sample::Sample), MALLOC_CAP_DMA);
 
   sFileSource.reset(
       new FatfsAudioInput(sServices->tag_parser(), sServices->bg_worker()));