Okay, just going off of what you posted, these are used dipes?? And you've possibly been using too much detergent? I would suggesting stripping your diapers immediately. (Build-up of detergent can cause repelling diapers. This can result in rashes/leak issues.)
There are MANY methods to do this...one is to wash on HOT with a little bit of Dawn instead of detergent and continue with this until there are no more bubbles in the rinse cycle, another is to boil diapers in water on your stove, to wash without detergent in the dishwasher until there are no more bubbles in the rinse cycle, or to wash on HOT using oxyclean instead of detergent and continuing until there are no more bubbles in the rinse cycle. Every time you wash, you'll want to look in the washer during the rinse and make sure there are no bubbles. If there are, continue to rinse until bubbles are gone and try using less detergent next time....yes, it's a delicate balancing act!!
Also, there may be bacteria/yeast in the diapers if they are used and haven't been properly stripped....after stripping you may want to begin using Tea Tree Oil (I usually use 3-4 drops for medium load) in your HOT wash cycle as an anti-fungal. I also usually strip my diapers (just in case) every 2-3 months.
You may also need to investigate and see if your detergent is okay to use with cloth diapers. I've found that most liquid detergents aren't. The most commonly used are Allen's Naturally, Charlie's Soap (which can cause rash), Dawn, or Sun. I personally use Nellie's Laundry Soda which hasn't caused me any build-up or repelling issues.issues.
If these items are new, there is prep work needed before use. Most AIO's need to be washed 2-3 times before use. Some prefolds need to be washed up to 12 times before use in order to maximize absorbancy. IF this prep wasn't done and combined with possible detergent issues, I'd still strip the diapers just to make sure.
I'm not sure about powder, I've never used it!!!...it's hard to find rash cream that won't buildup on your diapers and cause repelling and I was trying to see if using a cream could have been contributing to your diaper problems!!
You should be able to go online and see what weight your covers fit...That could be an issue as well.
Okay, hope that helps!! You may want to browse on diaperswappers.com...it's a huge CD community and you may be able to find answers there as well!!