No Sound in Phone Calls for Nexus 5

The sound during phone calls on my Nexus 5 recently stopped working, and after several days and much frustration, I figured out the cause and a possible work around. The problem started when I was trying to connect the Nexus 5 to a Plantronics wireless headset base with a three-pole plug–I now think it needs a four pole plug to connect to the Plantronics. Around this time the audio stopped working, but started working again briefly when I updated to a new Android security level. Because of the software update, it looked like the problem was a software problem, but it now looks like it is a problem with a connection on the headphone jack that tells the phone that a headset is plugged in even when one is not present.

Here are the symptoms:

• Phone calls do not work with normal phone-to-ear operation; neither party gets sound
• Phone calls work with speakerphone setting
• Phone calls work with Bluetooth headset
• Phone calls work with a wired headset.

The sequence that follows is not the sequence that I used for problem determination, but this is probably the easiest and least destructive approach. Although this is written for a Nexus 5 running Android 6.0.1, this approach will probably work for most Android phones.

Check Volume Settings

Make sure that volume is turned up for music, notifications and phone connections and that it is not in silent mode. This sounds insulting, but you should always start with the easiest to fix problem. Make sure to look at all of the volume levels by pulling down all of the volume controls as shown in Figure 1.

Check Permissions–Non-destructive Check

Next, check permissions for phone app and make sure that it can use microphone and the phone, as shown in Figure 2. If you are running an Android level below 6.0, this option will not be available. If you have not customized permissions, it is unlikely that this is a problem, but it is an easy check and a good opportunity to learn about permissions if you are not familiar with them.

Check for Misbehaving Applications–Non-destructive Check

Next, reboot the phone in safe mode by holding the down volume control while the phone is booting. If things work at this point, you probably have a misbehaving application that is grabbing control of audio and not allowing the phone application to get control of audio. This YouTube video demonstrates putting a phone into safe mode, but all you do is press the power button to bring up the shutdown panel, and then do a long press on the power off panel until the safe mode panel comes up. Figure 3 shows the safe mode panel that occurs when you press and hold the power off panel. Figure 4 shows the safe mode indicator in the lower left of the display that shows that you have successfully entered safe mode.

Check for Headphone Jack Problem

To check for a problem in the headphone jack that continuously tells Android that a headset is plugged in when one is not present, install the Soundabout app from the Google Play Store and manually assign the phone audio to the built-in speaker. Configure the phone app to use the earpiece as shown in Figure 5. If this works, you probably have a dirty or broken headphone jack that makes the hardware think that there is a wired headset connected when there is not. Repeated audio jack notifications like the one in Figure 6 are a strong indication that this is the root cause of the problem. At this point you can either live with the inconvenience of reassigning audio in Soundabout whenever you want to use Bluetooth or a wired headset, or you can get your phone repaired.

Some people have reported that repeatedly inserting and removing an audio plug has fixed this problem.

Permanent Software Workaround

If you know that the headphone jack is causing the problem and do not want to spend the money to have the phone repaired, you can disable the headphone jack using Soundabout, as shown in Figure 7. Disabling the jack will allow the phone to auto-select between speakers, earpiece and Bluetooth as it would normally. You can still use the headphone jack, but using this approach you will have to open Soundabout and re-enable the headphone jack before you use it.

Check Permissions–Destructive Check

If the audio jack is not broken, you can next reset all permissions to defaults, to make sure that it is not a permissions problem related to some other application that the Android phone app uses for something. This is probably a long shot, but it is substantially less time consuming to reset your customized permissions than to do restore data from a factor reset.

Check for Misbehaving Applications–Destructive Check

At this point, you can try a factory reset and restore apps after the reset, assuming you selected the backup options in your Android configuration. This will wipe out all of your data and customization. Even with backups, it will take a couple of days to get all of your apps working again. If this works, the problem was probably in some complex software configuration mess. Figure 8 shows the settings panel where you can perform the reset.

Check for Misbehaving Applications–Really Destructive Check

As a final resort, you can try a factory reset without restoring your apps. This wipes out everything and gives you a base phone. If this works, it means that one of your apps was misbehaving. Add them back one by one to figure out the problem.

Potential Hardware Repairs

I found a Youtube video, FIX: Nexus 5 Mic not Working which describes a possible cause and fix for this problem.