Yo don't give the Sony model, but with any reader its not good news I'm afraid. If the resets - try the hard as well as soft, you'll lose the content whether or not it works, but worth a try - don't work, the screen is almost certainly gone. You can also try giving it a really good charge-up, that may help.
However, you don't describe it, but I'm presuming it has a dark grey/brown look, lines across, white part-screen appearance, or half screen OK other not, or basically a wierd-look. This is classic sub-strata failure, exactly the sort of damage you would expect from the treatment you describe i.e. the placing of a heavy-ish object on the screen, perhaps with a fairly sharp impact.
I'm not sure a radio proximity would disrupt the screen - it's usually the thin glass screen e-ink layer below the upper plastic layer that goes, the screen may not look cracked as such. Perhaps someone else knows more about magnets & readers, but it's probably more likely do be physically damaged. Twisting forces are more likely to do damage, but impact can also, obviously.
Only solution is to replace the screen, which is very expensive.
You'll need to contact Sony support, and ask there, but the last I heard, the cost of repair - especially considering the price of the T1 has reduced in some places - is not far off the price of a replacement.
I don't think anyone does any reader screen other than the manufacturers.
[And, no definite news yet, but Sony usually come up with new versions in the autumn ................?]
Time to have a chat with the CB radio owner I think.......
Incidentally, any reader is open to this risk, not just Sony - and regretfully, that's why a cover is always a good investment.
Hope you find a solution.
Message was edited by: carpetmojo
