Q: When I'm in a Zoom video meeting, my audio is fine at first. But if I mute myself, then unmute, my audio is hard for other call participants to hear. The only fix seems to be to leave the meeting then rejoin it. Also, I use a Logitech external camera-microphone unit. What can I do?

Joel Boon, Shakopee

A: Because you are using an external camera with a microphone, any Zoom call you are on involves three sets of audio controls — those in Zoom, on your computer and on your camera-microphone combination. Toggling from mute to unmute on Zoom might affect any one of them, so be sure each one is unmuted and the volume is set appropriately.

Here are some other possible causes:

• USB and Bluetooth connections. If your camera-microphone unit plugs into a computer's USB port, try using a different port (some ports don't provide enough electricity to power digital devices.) If your camera-microphone unit connects to your computer via wireless Bluetooth signals, be sure its battery is adequately charged and that the device isn't dropping its Bluetooth connection. (See tinyurl.com/ybzs8gta).

• Other apps running on your computer. Zoom and other internet video services are data-intensive, so shut down any other apps that might be trying to use your internet connection or your computer's processor chip during a video call.

• Background noise. Noise near your computer can make it hard for others on a Zoom call to hear you. The Zoom app has settings that can suppress background noise so that you can be heard more clearly (see tinyurl.com/y689nbjs).

• Feedback. If anyone on your Zoom call is connected with both a computer and a phone, it can cause an echo or the squeal of audio "feedback" that makes it harder for participants to hear. Feedback can happen when an incoming sound is played on a computer's speakers, then picked up by the phone's microphone and fed back into the Zoom conversation. The same thing can happen if anyone's computer microphone is too close to his or her external computer speakers.

Q: I read your response about fixing location services on an iPad (see tinyurl.com/y89otsly). I don't believe that iPads or iPhones receive GPS satellite signals and instead get location information from one or more cell towers. Am I right?

Jim Shock, Colorado Springs, Colo.

A: Partly. The iPhone and some iPads (the Wi-Fi + Cellular models) really do use GPS satellites to identify your location. But GPS signals aren't available when you are inside, so the devices then use what Apple calls "assisted GPS," which combines data from nearby cell towers and Wi-Fi hot spots to approximate your position (see tinyurl.com/ycpuxzw3).

Q: I haven't used online printing. How can I print some of the 2,500 photos on my iPhone 7?

Angie Dziadzio, Enfield, Conn.

A: Click the App Store icon on your phone. Then type in the name of a top-rated online printing service (see tinyurl.com/y7u2pdkn), such as Shutterfly, Snapfish, Walmart Photo, CVS, Walgreens, Nations Photo Lab or RitzPix. Click "Get" and then open the app for directions.

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