When recording, especially to digital formats like this, it is important to monitor the recording levels, whether from a microphone or line input or whatever, and ensure they do not clip. Most recording apps have a level meter that clearly indicates the max level you should allow. By adjusting to meet this level, you will be able to determine whether it needs to be amplified or not.

The other thing is to not have the level too low. This allows background noise/hum/etc to increase in your recording. It also wastes some of the resolution of the audio capture device (the analog to digital conversion). This is why you should avoid having to increase the volume level later in ffmpeg or whatever processing you do.

So, set it to be close, but NOT exceeding the max level before clipping.