B737 pilot reported rejecting a takeoff in response to a spoiler configuration warning horn. Pilot stated there is an increased frequency of these warnings and recommended maintenance action to determine the cause.

Narrative

I believe there may be a trend on the B737 for spoiler related takeoff configuration warning horns. Possibly it is maintenance related and the spoiler levers or the micro switches need to be adjusted. We aborted our takeoff from XXL out of ZZZ on a B737. The spoiler lever was in the slot; I selected TOGA and got the configuration warning horn. I clicked off the throttles and aborted the takeoff; while less than 20 kts. The First Officer (FO) had immediately reached up and banged the spoiler lever and the alert went silenced. He did it before I even got the throttles to idle. But; we aborted the takeoff anyway; per the SOPs. We taxied off the runway; performed the before takeoff check and our second takeoff attempt was uneventful. The FO said the spoiler lever didn't move at all when he banged the lever to turn off the alarm. It was in the slot. The FO was an Air Carrier X 737 sim instructor and the previous day he told me he had experienced 2 spoiler alerts during takeoff in the previous three weeks. This would be his third event in as many weeks. While we were waiting to take off behind another Air Carrier Y 737 from Runway XXL; they also aborted their takeoff right in front of us; for a spoiler related takeoff configuration warning horn. So that made it 4 takeoff spoiler related warning horns the FO has seen in three weeks. I've never seen the spoiler cause a takeoff warning horn in my couple thousand hours in the 737 from the right or left seat.The spoiler may not have been seated all the way into the closed and locked slot. But; the FO stated that while he pushed on it to reseat the spoiler; while I was aborting the takeoff; he could not feel any downward movement. Once off the runway I pushed down on the spoiler handle and it was definitely seated. However; I noticed that there was the slightest play in the spoiler forward and aft; while it is in the slot. I don't know whether that is related to the micro switch not being activated.I realize we are waiting for the new configuration button to push; prior to takeoff that may resolve this issue. I am also aware Boeing states that cycling the throttles back and forth prior to takeoff; over time; may damage the fuel control. But the FO said for decades Air Carrier X procedures have been to quickly cycle each throttle forward and back to idle; while taxing to the runway. They do only one throttle at a time and quickly; so as not to cause any change in thrust. He also said when he flew 737's for Air Carrier Z; they would also cycle the throttles prior to take off. His assumption is that Air Carrier Y is the only company that doesn't cycle the throttle prior to take off. Of course; that is only one pilot's opinion; without any data. While on the other aircraft type; we also cycled the throttles before takeoff. We did both throttles simultaneously; since the engines were much slower to respond. Granted; while in the Military; it was never a procedure to cycle the throttles to check takeoff configuration prior to takeoff. But; something is causing the increased frequency in spoiler related configuration alerts and it maybe maintenance related.