The biggest challenge in 3G2 files is the audio, because most depend on AMR compression, originally built for early mobile networks rather than for editing or high-quality playback, using intense compression that removes most non-speech frequencies so voice could transmit over unstable 2G/3G links, making it useful then but outdated now; newer codecs like AAC and Opus outperform it easily as phones gained storage and faster networks, and since AMR was tied to telecom standards and licensing rule...