I'll turn it over to Emery:
Back in Washington, on Monday, October 1, [Woods] came to the president in some panic. She thought she might have caused a small gap in the Haldeman part of the tape. She had been on the telephone while using the foot pedal of a Uher machine supplied that morning for faster working. There was now a buzzing sound while she had been on the phones for four or five minutes.
For now, Nixon didn't share this with anyone else; during the continuing fight over the tapes, it was secret even from his lawyers. By the time they found out about it, the infamous gap was a good deal longer.
I have another nice source that I may use now: Elizabeth Drew's Washington Journal. Unlike most of the other things I've used so far, Drew is covering the "outside" portion of the story. But the events of October, especially, are at least to some extent an outside story.
On October 1, Drew mostly writes about campaign finance; there's been a Common Cause lawsuit, and it's now produced revelations about the money that the Nixon campaign raised and spent, especially just before the new campaign finance disclosure law went into effect in April 1972. As we saw back then, it was relevant to Watergate in particular, but to Drew in October 1973 the lines are blurred between Watergate and the other Hunt/Liddy operations; campaign finance law violations; and simply the raising and spending of huge sums of money, much of it from business interest groups.
So we're in October. The scandal has been at fever pitch all through the summer in public, but in something of a holding pattern behind the scenes ever since the collapse of the cover-up, the appointment of the special prosecutor, and then the revelation of the tapes. That's about to end.