ok I've been testing this over the past couple of days.
I did an initial test with using the same file but direct from the SD card in the Melzi and no reset jumper. First print was a total success and I thought I'd solved it. However, second print failed 1/3 in. Same issue where it just stopped mid print with no error.
So last night I went over the whole machine, snugged up all bolts, screws and double checked all electrical connections. The printer is on my office desk and is plugged into an extension cord, along with various other devices. They all lead back to the same socket on the wall. I decided to reconfigure everything, so that the printer plugged directly into the wall. Next to the printer I had a RPI setup with a camera for monitoring prints. I took that out of the mix for the time being. Then I ran a print with only the PC and the Printer powered on. So far I haven't had a stall out of 3 prints. 3d printing service chndigarth kochi bhopal
The only other thing it might be is some LED strip lights that I ran around my desk and above the printer. I don't know why they would be causing an issue, but it's the only new electrical addition since the problem started. Tonight I'm going to run some test prints with the LED lights on and see if it fails. Otherwise, it may have been some sort of electrical noise through the extension leads.