It sounds like you are doing everything you can to get the readings back to clarity, @walter- nice! 
I know it hasn’t been very long yet, but do the cards seem to have their old reliance back?
Francisco raised a really good point that reminded me of Cross-Checking with Different Divination Methods. Clarity is being lost someone along the line- maybe consider double-checking or backing up your readings with another method of divination? If your cards are still being moody, cross-checking may help you pin-point whether it is the cards or something else (lack of meditative focus, bad energy, etc.) blocking your readings 
And since you mentioned a new deck- your intuition may be going along with @MeganB’s solid advice: it could definitely be time to give this deck a vacation! 
I’m always an enabler when it comes to getting new tarot decks- they are dangerously fun to collect 
Do you have a new deck in mind that you are interested in, Walter?