Powering LED Strip at both ends shorts my psu?
Put a diode to every psu cable or just take only one psu but make a connection between the input and the far end eith a cable of more than 0,5 mm^2... Spesker csble or so. 

Problem with two psu is: one gives 5,00 Volt,  the other 5,05... And there is s power of 0,05 Volt / 8 Ampere running.  

Second problem can be the influrnce of different PSU switching frequencies. 
Regards,  Michael