您可以使用按主机api设备索引获取设备信息。
例如：

import pyaudio

p = pyaudio.PyAudio()
info = p.get_host_api_info_by_index(0)
numdevices = info.get('deviceCount')

for i in range(0, numdevices):
    if (p.get_device_info_by_host_api_device_index(0, i).get('maxInputChannels')) > 0:
        print("Input Device id ", i, " - ", p.get_device_info_by_host_api_device_index(0, i).get('name'))

我还没有看过pyaudio，但我也在一些场合使用过sounddevice。
下面是一个示例代码，列出了可用的input和outputaudio devices。

import sounddevice as sd
print sd.query_devices()

正如您可以从下面的输出看到的，当我把我的耳机麦克风插孔，Index 1是可用的输入。1 Jack Mic (IDT High Definition A, MME (2 in, 0 out)
而默认笔记本电脑音频麦克风显示为index 2
2 Microphone Array (IDT High Defi, MME (2 in, 0 out)

输出

Python 2.7.9 (default, Dec 10 2014, 12:24:55) [MSC v.1500 32 bit (Intel)] on win32
Type "copyright", "credits" or "license()" for more information.
>>> ================================ RESTART ================================
>>> 
   0 Microsoft Sound Mapper - Input, MME (2 in, 0 out)
>  1 Jack Mic (IDT High Definition A, MME (2 in, 0 out)
   2 Microphone Array (IDT High Defi, MME (2 in, 0 out)
   3 Microsoft Sound Mapper - Output, MME (0 in, 2 out)
<  4 Speakers / Headphones (IDT High, MME (0 in, 2 out)
   5 Communication Headphones (IDT H, MME (0 in, 2 out)
   6 Primary Sound Capture Driver, Windows DirectSound (2 in, 0 out)
   7 Jack Mic (IDT High Definition Audio CODEC), Windows DirectSound (2 in, 0 out)
   8 Microphone Array (IDT High Definition Audio CODEC), Windows DirectSound (2 in, 0 out)
   9 Primary Sound Driver, Windows DirectSound (0 in, 2 out)
  10 Speakers / Headphones (IDT High Definition Audio CODEC), Windows DirectSound (0 in, 2 out)
  11 Communication Headphones (IDT High Definition Audio CODEC), Windows DirectSound (0 in, 2 out)
  12 Communication Headphones (IDT High Definition Audio CODEC), Windows WASAPI (0 in, 2 out)
  13 Speakers / Headphones (IDT High Definition Audio CODEC), Windows WASAPI (0 in, 2 out)
  14 Jack Mic (IDT High Definition Audio CODEC), Windows WASAPI (2 in, 0 out)
  15 Microphone Array (IDT High Definition Audio CODEC), Windows WASAPI (2 in, 0 out)
  16 Headset Microphone (Bluetooth Hands-free Audio), Windows WDM-KS (1 in, 0 out)
  17 Headphones (Bluetooth Hands-free Audio), Windows WDM-KS (0 in, 2 out)
  18 Headphones (HpOut), Windows WDM-KS (0 in, 2 out)
  19 Microphone Array (MicIn2), Windows WDM-KS (2 in, 0 out)
  20 Jack Mic (MuxedIn), Windows WDM-KS (2 in, 0 out)
  21 Dock Mic (MuxedIn), Windows WDM-KS (2 in, 0 out)
  22 Rec. Playback (MuxedIn), Windows WDM-KS (2 in, 0 out)
  23 Speakers (Speaker/HP), Windows WDM-KS (0 in, 2 out)

在PyAudio文档中，它声明您可以定义input_device_index。
要找出该设备索引是什么，您可以按照此Github Gist中提供的代码或Raspberry Pi Forum上的代码（提供了输出代码的示例）进行操作。

您可以使用PulseAudio选择输入设备。

使用@slegroux awesome代码查找音频索引：

import pyaudio

p = pyaudio.PyAudio()
info = p.get_host_api_info_by_index(0)
numdevices = info.get('deviceCount')

for i in range(0, numdevices):
    if (p.get_device_info_by_host_api_device_index(0, i).get('maxInputChannels')) > 0:
        print("Input Device id ", i, " - ", p.get_device_info_by_host_api_device_index(0, i).get('name'))

找到要使用的麦克风的索引后，将input_device_index选项添加到www.example.com（）中，后跟麦克风的索引（在我的例子中，麦克风的索引为1）p.open，如下所示：

stream = p.open(
    format=FORMAT,
    channels=CHANNELS,
    rate=RATE,
    input=True,
    frames_per_buffer=FRAMES_PER_BUFFER,
    input_device_index=1
)

希望这对你有帮助！

我不了解PyAudio，但是对于sounddevice模块，它是这样的：

python3 -m sounddevice

只需使用arecord -l列出所有可用的输入设备。