Daas would reccommend audio sehaj paath of Guru Granth Sahib is available at ikatha by giani harbhajan singh jee:
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www.ikatha.com]
Also nitnem banis are also available by giani jee from the same site. Giani jee's uchaaran is closer to Jatha i.e. used of shh and z sounds.
Most of other paath files are from samprdayak background. The entire sehaj paath of Guru Granth Sahib by bhinder kalan (Baba Mohan Singh jee Bhindranwale jatha) is available at gurmatveechar.com. These files are also very useful because along with the paath the Giani jee (Bhai Harbhajan Singh jee Dhudikey) also gives commentary and guidance on uchaaran and bishraams.
Hopefully, audio files will begin to appear on this site for nitnem and sehaj paath. These files are needed for those that want to do uchaaran of Gurbani based on viaakaran (grammer), the use of z, shh letters and bindia at correct places.