Why would the prompt get overwritten?

p_ash-3.2$ cp some_file1234.html /some/loc/ation/ofthe/some_file1234.html.html_Backu

Have been seeing this intermittent issue with the command-line, while typing longer lines as part of any command, after typing some characters, say about 70, it starts all over again, from the extreme left, even before the -bash-3.X$ consequently the prompt and first few characters of the command itself gets overwritten, why would this happen, any workaround?