Dear @jay_s_uk ,
I did as you said, just replaced the Sandisk with good old Toshiba 8gb class 4 and uploaded the 140mb file.
Worked without any issue, case closed, THANK YOU very much 
I'll invest in new cards.
SD card 0 detected, interface speed: 25.0MBytes/sec
SD card longest read time 1.3ms, write time 43.3ms, max retries 0