The lecture recordings can be played at higher speed.
Tips
culture
倍速播放 became a defining behavior of Gen-Z / millennial Chinese viewers — playing dramas and lectures at 1.25×, 1.5×, even 2×. Sparked plenty of think pieces about shrinking attention spans (注意力危机). Common shorthand: 倍速看剧 'speed-watch a show.'
usage
倍速 alone (a noun: 'multiplied speed') suffices in casual chat: 我开倍速 'I turn on faster playback.' 0.5倍速 = half speed; 2倍速 = double speed.