Lexus GX 2004-09 :: Hard Start - Vehicle Sometimes Takes 3 Or 4 Tries Of Turning Key Before Engine Fires Up

Over the last week my GX has developed a strange issue. It sometimes takes 3 or 4 tries of turning the key before the engine fires up. It turns over strongly and quickly but it isn't "catching". The weird thing is, it doesn't happen every time. Here is what I have noticed:

1) Leave the vehicle parked overnight - no issues starting. It starts right up.

2) Crank the vehicle after having only been off a few minutes (like after you run in to pick something up at the grocery store) it cranks right up.

3) Let the vehicle sit for between 1 and 4 or 5 hours and the problem appears. It turns over and over and over but won't actually start. Anywhere between the 3rd and 5th turn of the key it will finally catch and actually crank.

In all cases, once it cranks it runs smoothly and normally with no issues.

I have replaced the battery thinking that was the issue but that did not fix the problem. Also strange is the fact that this problem occurred after I replaced both front door speakers, an operation that required me to have one or more doors open for an hour or so at a time (hence why I thought it might be a weak battery).