Small town in Oregon here (all measured along the routes walked, not ‘as the crow flies’):

• Convenience Store: ~150 meters, right down the road
• Supermarket: Will get back to later
• Bus Stop: The local bus company runs a loop around town so there’s technically one closer to my house than the convenience store, but the busses that can take you to another town stop at the one ~400 meters away.
• Park: Three parks, which are ~400, ~500, and ~580 meters away respectively, though there’s not much of anything at the 400 meter one but some sports fields.
• Big Supermarket: Will get back to later
• Library: ~500 meters (the 500 meter park is right across from it)
• Train Station: 29 kilometers by car to the nearest passenger rail station I can find. Without a car I’d need to walk ~400 m to the bus stop, take a $1 bus ride with the local company to Town B, then take another bus ran by this town’s company, and then walk another ~480 meters because they don’t have a stop at the station. Google Maps predicts that trip will take about 1 hour 20 minutes one-way, and it would cost $2 (or $4 round trip).

Now, I’m not entirely sure what separates a supermarket from a “big supermarket” in your mind, because to me all supermarkets are quite big by definition, so I’m going to explore three different trip options: one each to two supermarkets in or near my town, and one to the nearest Walmart, which I’m 100% sure should count as a “big supermarket”, but which is a couple towns away.

• Supermarket A is close enough that walking to it is a viable option, which would be ~730 meters to the edge of the parking lot or ~875 meters to the front of the store. Alternatively, if I can plan the scheduling of my trip around it or I’m not picky about the timing I can walk ~100 meters to the nearest stop in the city bus loop, wait a while, and walk of right at the front.

• Supermarket B is 2.6 kilometers by foot, but a large part of that trip is walking along the side of a lightly-developed highway with no sidewalks, so I don’t consider walking here a viable option. By bus it’s the same 100 meters to the bus stop, wait, then directly to the storefront.

• The nearest Walmart is ~25 kilometers away by car, but the local bus company doesn’t offer a direct route to that town so I have to take a bus to Town C, take the Town C Bus Company’s bus to the east edge of Town D, then take Town D’s bus to the Walmart on the western edge. Google Maps says this would take just over 2 hours one-way, and it would cost $2 ($4 round trip) because Town D’s busses are all free to ride at the moment.

I’m not sure how to stop the DAC from shutting down when Mint goes to sleep, but maybe you can avoid the problem by making Mint not go to sleep in the first place? There’s an option for it in the System Settings program, in the “power management” menu (under the “Hardware” heading).

Try doing that and see if the problem keeps happening. If it keeps happening, the DAC shutting down was probably caused by something else.