Bugs and Suggestions

Sorry, I didn't mean to sound so negative. 😔 I really hope you'll fix it, but so many bugs have appeared that it's hard to believe they'll all actually be fixed. 😢

NiyaOct 13

Hello again! I’ve carried out some additional tests to help investigate the audio issue I reported earlier.

I compared two video files:

* GOOD.mp4 - plays normally in Telegram.
* BAD.mp4 - produces electronic interference-like noises whenever any sound is playing.

Both files have very similar technical specifications: H.264 High Profile video at 1920×816 and approximately 23.976 fps, as well as AAC-LC stereo audio at 48 kHz.

Here’s what I’ve discovered through additional testing:

* The affected file plays with clear audio outside Telegram on the same iPhone.
* The issue persists even after the video has been fully downloaded to the device.
* Completely replacing the original audio track with a different one did not resolve the issue.
* Remuxing the file without re-encoding its streams did not help.
* Re-encoding only the video did not help.
* Re-encoding the entire audio track to AAC or ALAC did not help.
* Re-encoding both the video and audio from scratch, even with reduced video quality and audio bitrate, did not help.
* The video itself displays correctly in Telegram. The interference occurs only when audio is playing and disappears during silent scenes.
* Both original files decode without errors using FFmpeg on a computer, and the extracted audio from the affected file sounds normal when played separately.

Based on these tests, the issue appears to be related to how Telegram’s built-in iOS player handles certain video files. However, I haven’t been able to determine the exact cause.

I wanted to share these additional findings in case they help with your investigation. Thank you!

Admin DogOct 13· Edited

Niya

Thanks for the additional info.

Guelfo Alexander GhibelliniOct 18

I recorded the two good and bad audio quality with a separate phone (Android) and sent them in a bug report, but they were lost due to the merging of my report to this one, so I attach them again here.

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NiyaOct 18

I’ve also noticed that, since October 9, in addition to everything else, the synchronization between the audio and video tracks in Telegram’s iOS player has gotten worse. Either the video lags slightly behind the audio, or the audio plays slightly ahead of the video.

Please look into this issue as well and fix it if possible.

This is not just a subjective impression, but the result of my own observations. I compared the same videos with hardcoded subtitles on different devices. When watching the videos on Android and Windows, the subtitles appear at the right time, whereas on iOS, they noticeably lag behind the audio. In other words, the person has already started speaking, but the subtitles appear with a slight delay.

This issue occurs both when watching videos with headphones and when watching them without headphones.

Steps to reproduce

Current result

Expected result

Device info

31003 Cards