Please adjust the upload timeout for image upload or allow us to cancel an upload! I am tired of waiting 10+ minutes for it to FINALLY give me the error message that an image can't be uploaded. It usually works the second time I try to upload the same image.
It sounds more like you operating system or device rather than Etsy. It could be your ISP is timing out too soon.
I seldom have problems uploading. The few times I have the upload took only a couple of minutes rather than the 30 seconds it normally takes.
Try resetting your modem