Hopes that digital-music sales would pick up in Japan after a lackluster first quarter have been dashed.

In the April-June second quarter, the 54 member companies of local labels body the Recording Industry Association of Japan (RIAJ) sold 115.4 million units of digital product, down 3% from the second quarter of 2008, for a retail value of 22.1 billion yen ($235.8 million), down 2%.

The disappointing results were mainly due to a 12% drop in mobile-based master-ringtone sales to 39.8 million units, for a value of 4.1 billion yen ($43.7 million), down 18%. Sales of ringback tones, in contrast, rose 14% to 27.4 million units, for a value of 2.4 billion yen ($25.6 million), marking a 20% rise over the second quarter of 2008.

Sales of mobile-based full-track downloads fell 4% to 34.7 million units, for a value of 12 billion yen ($128 million), unchanged from April-June 2008. 

Overall, mobile-based downloads fell 4% in the second quarter to 104.1 million units, for a value of 19.4 billion yen ($207 million), down 2%.

Sales of PC-based music downloads, meanwhile, continued to grow steadily, rising 10% to 11.4 million units, for a value of 2.4 billion yen ($25.7 million) in value, up 8%.

But the growth in PC downloads still isn’t enough to revive Japan’s digital-music market, which until recently posted strong growth as new products and services were rolled out.

PC downloads comprise singles, albums, mini-albums and other content sold over wired networks, according to the RIAJ, and albums and mini-albums count as single units regardless of the number of tracks they contain. Singles, however, constitute almost all PC-based download sales.

Cumulative digital-sales results for the January-June first half show a 3% drop in volume terms from the first half of 2008 to 233.7 million units and a 1% decline in value terms to 44.6 billion yen ($475.8 million).