a weird problem during transfer file on custome rom

hi every one i have a a weird problem been using galaxy note stuck rom for 1 year, from last 1 week i wanted to try a costume rom and i installed 2-3 differents roms all went fine no problem during installation. The only problem i have is when i connect to my pc to transfer files to either internal/external the files start sending with 3mbites transfer rates for example then drops to 300k then to 0k then goes back to 1mbiets then drops again to 0 while this happens the phone get freez and only way to hold power button to reset it

i just flashed back to stock rom and it just works fine there only this problem happens when im on costume roms