Image exporting badly - with sort of lines

Hi, 
when i publish indesign document, the button has this issue (pic). I tried to upload the button by copying directly from illustrator (ctrlc-ctrlv), then i tried uploading a png - still it does this. Can anyone help? It's driving me crazy. 

Yesterday more pictures had lines over them, all got fixed by reuploading. I'm afraid that at any given moment I will have to reupload everything again.