What is default behavior on playing prerecorded DCC cassettes is this:
When fully rewound, when PLAY is pressed, the deck will first encounter a few seconds of leader tape, which of course does not contain any information. The deck wil show ‘-- – --’ or similar in the display. This wil last around 2-4 seconds.
When the part with magnetic tape is reached, there will be a code on the prerecorded tape to instruct the deck to forward to the first track marker. This will be a bit further on the tape, so the deck will do a short FFW and when it finds this marker it will PLAY and the first track will start.
This is done because from experience (also from analog cassettes) it was learned that the first part of a tape after the leader tape is more prone be bad and could have dropouts etc. Further along the tape it is usually fine.
This writing of a ‘SKIP’ marker also happens when you make your own recording, when you follow the correct procedure to initialize a tape for a new recording. Then the deck will start writing a ‘LEAD IN’ while preparing for the recording (which will become the part that will be FFW on PLAY), go into REC PAUSE and wait for you to start the actual recording.
This procedure to correctly initialize a tape is different per deck unfortunately. I have written for myself a guide to do this correctly for some of the decks that I usually do my recordings on. You can read this quick reference guide here:
The DCC standard defines a few different ways to do a recording. It is explained in the manuals as well.
Now, I just realized that I explained a lot, but have not answered your question
It could be some grease residu from the internal felt pads that resides on the beginning of the tape. The tape will ‘stall’ and that will confuse the player. It has happened, and is well documented. It will cause the behaviour you describe. There are blog posts and youtube videos about this phenomenon.
It could also be that there is some other tape damage (like crinkled tape) which causes the information from the tape to be read incorrect and generate an ‘error’ in the electronics and that might confuse the player also.
You could check the tape at that point, very carefully as it is very delicate. And also make sure the head, the capstan and the pinch rollers are all pristine clean. There is a lot more to be said, but just start there.