Robert Park
Analyst · Rosenblatt
Thanks, Kevin, and thanks to everyone joining us on the call today. Before we review the quarter in some detail, I'd like to hit the highlights.
First, revenues for Q2 were just above the midpoint of the range we laid out in the Q1 earnings call, and profitability also came in above the midpoint of the range. Second, while the environment remains uncertain and dynamic, our guidance for the year remains unchanged. And third, as I have said before, we feel good about our long-term growth prospects. Our value proposition remains strong and our financials are solid.
Q2 revenue was $365 million, down 3% compared to the year ago quarter, but above the mid-quarter guidance we shared with you on the last earnings call. Licensing revenue of $338 million was down 4% year-over-year. Products and services revenue was $26 million, up 8% year-over-year. Our end market outlook for the full year is unchanged from last quarter's call. Detailed licensing performance by end market is on our IR website, but I'd like to point out some noteworthy details.
As a reminder, timing of recoveries, the minimum volume commitments and true-ups can drive volatility between quarters. Mobile is the biggest standout in the quarter, growing 151% sequentially, primarily due to timing. And although we saw a nice snapback from mobile in the quarter, we still expect mobile to be down slightly for the full year.
Similarly, you may notice that broadcast is down 18% year-over-year this quarter. This, again, is just about timing. As we have said before, we expect broadcast to be down slightly for the full year. We continue to expect solid growth in auto and a slight increase in PC. This increase will be offset by slight declines in broadcast, consumer electronics, mobile and to a lesser extent, gaming. While we see growth in Dolby Atmos and Dolby Vision in these markets this year, the overall revenue declines are primarily due to tough comps in terms of the timing and size of the deals.
Moving to the bottom line. In Q2, we earned $1.27 per diluted share on a non-GAAP basis, above the midpoint of our guidance, primarily due to stronger revenue, higher nonoperating income and lower taxes and we generated $181 million in operating cash flow.
Moving on, we repurchased $25 million worth of common stock and have about $107 million remaining on our repurchase plan authorization. We declared a $0.30 dividend up 11% from our dividend a year ago and ended the quarter with cash and investments of just under $1 billion.
Turning to guidance. There is still uncertainty in the market, and our guidance assumes no material change in the macroeconomic environment. While we continue to see steady growth of content created and distributed in Dolby technology and strong engagement from our partners, device shipments remain soft and the timing of deals can vary.
For Q3 fiscal year '24, we expect revenue between $270 million and $300 million. Within that, licensing revenue is estimated to range from $245 million to $275 million. Gross margin should be approximately 87% on a non-GAAP basis. We expect non-GAAP operating expenses to be between $180 million and $190 million. Our effective tax rate for Q2 is projected to be around 21% on a non-GAAP basis. So as a result, we estimate that non-GAAP EPS should be between $0.51 and $0.66 per diluted share.
Moving on to full year guidance. Coming into the year, we said revenue would be weighted more towards the first half of the year than the second half of the year. And midway through the year, that first half weighting is slightly more pronounced than we expected. First half revenue benefited from timing of deals that we expected in the second half of the year. For this reason, our full year guidance for fiscal year '24 is unchanged at roughly flat revenue.
In the second half, we are expecting a higher revenue weighting towards the fourth quarter due to the timing of deals. Taking a step back, our full year guidance, consistent with what we've been saying all year, reflects an assumption of a mid-single-digit decline in foundational audio licensing revenue, offset by a high single-digit growth in Dolby Atmos, Dolby Vision and imaging patent licensing revenue and roughly flat products and services revenue.
Non-GAAP gross margin should be roughly 89%. Non-GAAP operating expenses for the full year should be in the $740 million to $750 million range which will result in about a 1 to 2 percentage point improvement in operating margins on a full year basis. On the bottom line, we are expecting non-GAAP EPS of between $3.60 to $3.75.
To wrap things up, the creation and distribution of Dolby-enabled content continues to grow nicely and our partners are still very engaged. Our financials remain strong, and we are well positioned for growth when economic conditions improve. With that, I'd like to turn it back to the operator to open the line for your questions. Operator?