iPhone 16 Pro volume increases when opening TikTok

On an iPhone, Media Volume, Alarm Volume, Alert/Ringer Volume, and Call Volume are related but not all controlled by the same setting. 

1. Media Volume

This controls the sound produced by apps and media, such as:

YouTube and other videos

Music

Games

Podcasts

Most app sounds

Audio played through the iPhone speaker, headphones, CarPlay, Bluetooth, etc.

How to control it:

Press the Volume Up/Down buttons while media is playing, or

Open Control Center and move the volume slider.

The volume buttons normally control media volume when you are actively playing media.

2. Ringer / Alert Volume

This controls sounds such as:

Incoming phone calls

Text/message notifications

Mail notifications

App notification sounds

Calendar/reminder alerts

Other system alert sounds

Go to: Settings → Sounds & Haptics → Ringtone and Alerts

The Ringtone and Alerts slider controls this group of sounds.

You can also enable Change with Buttons. When enabled, the physical volume buttons can change the ringtone/alert volume when you're not actively controlling media.

Important: Turning media volume down to zero does not necessarily turn notification/ringer volume down to zero.

3. Alarm Volume

This is where there is an important distinction.

For Apple's Clock app alarms, the alarm volume is generally tied to the Ringtone and Alerts volume.

So if you set:

Settings → Sounds & Haptics → Ringtone and Alerts → 50%

your normal Clock alarm will use that level.

Changing the volume of a YouTube video, for example, doesn't change the Clock alarm volume.

Also, the Silent Mode switch does not silence a normal Clock alarm. That's intentional—otherwise it would be rather easy to sleep through an alarm.

4. Call Volume

There are actually two different "call volumes."

A. Volume of the person you're talking to

During a phone call, the side volume buttons control the volume of the other person's voice coming through the earpiece or speaker.

This is separate from your normal media volume.

For example:

You are listening to YouTube → volume at 70%

You make a phone call → you set call volume to 40%

Changing the call volume doesn't necessarily change your YouTube volume.

B. Ringtone volume

Before you answer a call, the incoming ringtone uses the Ringtone and Alerts volume described above.

Once you answer, the volume buttons control the call audio.

One particularly important iPhone setting

Go to: Settings → Sounds & Haptics → Ringtone and Alerts

You'll see the Ringtone and Alerts slider.

Below/around it you'll also find Change with Buttons.

If Change with Buttons is OFF, the physical volume buttons generally won't accidentally change your ringtone/alert volume when you're not playing media.

If Change with Buttons is ON, pressing the volume buttons when you're not actively playing media can change the ringtone/alert level.

So, if you want your alarm and notifications to remain at a fixed level, while freely using the side buttons for YouTube/music, keeping Change with Buttons OFF is usually the better arrangement.

Expressing or conveying auditory experiences effectively through these forums may be challenging. The underlying sound issue on your iPhone cannot be accurately diagnosed from a YouTube link. Factors such as your iPhone's specific sound settings, visual defects, and potential hardware problems cannot be assessed through this method. For more personalized and in-depth assistance, I recommend securing a Genius Bar Reservation and exploring the various support options provided by Apple.

Get a Genius Bar Reservation and Apple Support Options - Apple

When you encounter issues with your Apple devices, the Genius Bar at Apple Retail Stores is the go-to place for expert assistance. The Genius Bar is staffed by knowledgeable Apple employees, often referred to as "Geniuses," who can diagnose and resolve a wide range of hardware and software-related problems. To ensure personalized attention and a convenient visit, Apple provides the option to schedule a Genius Bar Reservation.

Contact Genius Bar.

Manage Reservations - My Reservations - Apple

They probably don't increase the volume, they could get a similar effect with compression. ITV used to do it in the old days of broadcast TV. The standards set the max volume but adverts sound was compressed to make it sound subjectively louder.

Apps can adjust their own playback volume relative to other audio. So TikTok could make its playback louder without changing the iPhone’s master media volume setting. That capability alone doesn’t prove TikTok is doing so in this case.

The Apple Developer article describes how app developers can manipulate the volume (within a preset range) in their apps.

https://developer.apple.com/documentation/avfaudio/avaudioplayer/volume

It is possible that TikTok app had manipulated the volume level which is not acceptable IMO

Go to App Store and in the TikTok listing look for a developer link and complain.

Leave a one star review there too

Hey Z, get yourself over here https://discussions.apple.com/thread/256387474 👏👏