220-1101 Mobile Devices Practice Question
A user reports that during phone calls, the person on the other end cannot hear them. The user can hear the caller clearly. The user can also record voice memos and videos with sound without any issues. Which of the following components is MOST likely faulty?
⚠ Common exam trap
Many exam-takers assume a microphone issue must affect all audio recording functions, but the CompTIA 220-1101 exam tests the understanding that noise-cancellation microphones are separate from the main microphone and only active during voice calls, not during voice memos or video recording.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Noise-cancellation microphone
The noise-cancellation microphone is the most likely faulty component because it is specifically designed to pick up the user's voice while filtering out ambient noise. During phone calls, the primary microphone handles voice transmission, but if the noise-cancellation mic fails, it can cause the system to misinterpret the user's speech as background noise and suppress it, resulting in the caller not hearing the user. The fact that voice memos and videos record correctly indicates the main microphone is functional, isolating the issue to the secondary microphone used for noise cancellation during calls.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Noise-cancellation microphone
Why this is correct
The noise-cancellation microphone is a dedicated input transducer that captures the caller's voice while using differential signal processing to subtract ambient sounds. During a call, the phone relies on this microphone (often with a secondary reference mic) to isolate speech; if it fails, the transmitted audio may be entirely absent or too corrupted to be heard, even though apps using the primary bottom microphone for voice memos or video still function.
- ✗
Earpiece speaker
Why it's wrong here
The earpiece speaker is an output-only transducer that converts the received electrical audio signal into acoustic pressure waves for the user's ear. Because the user can clearly hear the remote party, the earpiece is demonstrably operational, and it has no signal path from the user's voice back to the transmitter, so it cannot cause the far end to hear nothing.
- ✗
Loudspeaker
Why it's wrong here
The loudspeaker, used for speakerphone and media playback, is another output-only component that plays back received audio. Even in speakerphone mode, the actual voice pickup still relies on the microphone array; the loudspeaker does not feed any signal into the uplink path, and if it were defective the user would lose incoming call audio, not their own outgoing voice transmission.
- ✗
Charging port
Why it's wrong here
The charging port is a power and data interface, typically USB, that provides DC power for battery charging and differential data lines for file transfer. It contains no MEMS microphone element or audio front-end; while some USB standards carry digital audio peripherals (e.g., USB headsets), the port itself does not capture acoustic energy, so a malfunctioning charging port would not prevent the distant party from hearing the user.
Go deeper
Related to this question
About these practice questions
One of 896 original 220-1101 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This 220-1101 practice question is part of Courseiva's free CompTIA certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 220-1101 exam.