A TiVo software glitch is causing some set-top boxes to reboot repeatedly, though the company says it recently began uploading fixes to customers. UK TiVo users can take heart, however -- the bug won't affect them, as it only jams the integrated set-top boxes sold by US digital satellite service DirecTV. The problem affects only subscribers who have receivers and service from DirecTV . TiVo confirmed the problem with its digital video recording software and said it began downloading the fix to customers earlier this month. This is the second time in less than a week that reports have surfaced of problems with digital video recording software. The technology is just starting to catch on with consumers but apparently isn't ready for prime time yet. TiVo spokeswoman Rebecca Baer said only a small group of subscribers have been affected by the problem, though she wouldn't specify how many. "It seems that there are isolated incidents of people having problems," Baer said Tuesday afternoon. "The problems are tied to WishLists and searches for actors with single names [such as Madonna or Cher]." TiVo's service allows people to digitally record TV shows onto a hard drive. Its WishLists let subscribers program TiVo to search for shows with certain actors or directors and automatically save the programming. According to research firm Gartner, 35 percent of TiVo's 153,000 subscribers were using DirecTV receivers at the end of January. Subscribers have been posting complaints to Web forums for several months. The problem originates in TiVo's software, version 2.0, which was released when DirecTV receivers first began shipping in late 2000. The glitch causes the set-top box to reboot repeatedly, preventing viewers from watching their saved programs. The DirecTV receiver with TiVo service is a set-top box that picks up satellite television and allows viewers to store the programming onto a hard drive. TiVo provides the digital video recording service, which is billed in combination with DirecTV subscriptions. The combination service costs $22 to $83 per month. Hughes, Philips and Sony sell the DirecTV receivers for $399. One owner of a DirecTV receiver with TiVo service who had replaced his original unit with a new one wrote on a Web forum: "Over the course of last week, I added a large number of wish list items... Yesterday, the rebooting started on this replacement unit." Another person wrote: "It started the reboot-every-20-minutes thing. It doesn't matter what I'm doing; it will just reboot -- very annoying obviously." TiVo isn't the only interactive TV company facing software glitches. An unrelated software bug was discovered in set-top boxes with Microsoft's UltimateTV service. UltimateTV combines elements of Microsoft's WebTV -- a television-based email and Web surfing service -- DirecTV satellite service and digital video recording. Gartner analyst Mark Snowden said such problems do not bode well with consumer electronics buyers who -- unlike PC buyers -- may be less familiar dealing with upgrades. "Those in the PC world have been conditioned to expect that things don't work out, but consumer electronics is a whole different world," Snowden said. "People expect things to work on a TV." Baer said that unlike the UltimateTV bug, the problems with the TiVo boxes have occurred with a small number of people and are already being taken care of. The company is downloading the fix with its updated software -- version 2.01 -- to batches of customers through May. The update is being downloaded to all set-top boxes with TiVo service including so-called stand-alone boxes. After initially trying to sell the digital video recording service in stand-alone boxes, companies are beginning to realise that digital video recording needs to be combined with other features to attract subscribers. "Set-top boxes with integrated features are the part of the future for TiVo, and DirecTV will play a major part of that future," Snowden said. The company expects 50 percent of new TiVo subscribers this year will use DirecTV receivers. In a software update for DirecTV receivers planned for this summer, TiVo will activate a feature allowing viewers to record a show on one channel while watching a different show on a separate channel. Have your say instantly, and see what others have said. Click on the TalkBack button and go to the ZDNet News forum. Let the editors know what you think in the Mailroom. And read what others have said.