That is the code you get when you are using a panasonic remote but the remote is programmed to a different code than the dvd player. Are you mistakenly using a remote from another panasonic unit? If not, it is possible some how the remote code got changed on the remote or the unit. just get them back on the same code. (I.E. code 1, or 2 etc..)
Actually, you can test whether it is a remote code problem by seeing if the remote will turn on the unit. If the front display brightens and then dims, you have the wrong code. (My HS2 has auto dimming turned on).
Someone could also have programmed the HS2 to respond to code 2, i.e., your remote may still be putting out code 1 requests, but your HS2 filters on code 2. My RP-91 runs on code 1 and the HS2 runs on code 2. Thank goodness for this feature.