When exporting a WEM from Wwise, it normally lacks the seektable needed for fast-forwarding. For 99% of WEMs, this isn’t a big issue, but for cassette tapes, it poses a moderate issue.
To enable the seektable (and a whole lot of other things which help when exporting Wwise thingys for TPP, which include conversion settings for Voices (Vorbis + Embed filename marker for subtitles), Demos (Vorbis + 4096 granularity table) and Tapes (Vorbis + 8192 granularity table)), simply place the downloadable WWU file below (made by caplag) into your Wwise projects “Conversion Settings” folder, eg: C:/Users/<insert your own username>/Documents/Wwise Projects/<name of your Wwise Project>/Conversion Settings.