[Skrillex]

For that visual part, I think that that is the case for most people, including those without aphantasia. From what I have gathered from personal experience and by talking to other people, this so-called mind's eye is (somewhat unintuitively) not really related to your actual eyes, so closing them would not necessarily lead to you seeing things. When I personally know something strongly enough to "see" it without it being in front of me, it feels more like I begin to momentarily stop focusing on the input from my eyes and instead prioritize that thing. It is not like overlaying some images over what I am seeing with my eyes (although some people are apparently able to do this also), but rather I temporarily ignore my eyes and am more interested or focused on this alternative source. This is an entirely* voluntary process and can in fact require some effort on my part depending on how corrupted the data is, but I could not say how it is for others. The images are not at all intense or of high fidelity, and failing to focus on them is sufficient to stop seeing them for me. I might just have relatively weak image visualization though.

I am not sure if I have any meaningful anecdotes regarding reading fiction. I do not believe I have seen or otherwise visually imagined the events in either fiction or non-fiction most of the time unless reading it made me recall something that I remember. It might be possible if I were actively trying to do that, but I can say that whatever experience I am extracting from reading fiction is not primarily due to being able to see it. If people are really imagining that sort of thing automatically, I feel pretty envious of that myself.

When it comes to sounds though, I am something of a captive in my own mind. For the majority of the period that I am awake and not highly focused, my mind is using approximately 98% of its resources to replay, construct, combine, and modify music. This is usually much more interesting than what I am hearing and what most people have to say to me, and it can require conscious effort to hear the latter. Unlike the images, this sound is of high quality and is not at all consensual. I have been told that this is not quite normal. In hindsight, this could have been a useful trait had I worked with it instead of worked through it.

*Assuming that these memories are not brought on through involuntary means, such as some drugs and trauma-induced flashbacks.